ML102871019

Engineering Change Package 75219, Rev 0; Reactor Building 28 Undated Delamination Repair - Phase 3 Concrete Removal

ML102871019
Person / Time
Site:	Crystal River
Issue date:	09/20/2010
From:	Progress Energy Co
To:	Office of Information Services
References
FOIA/PA-2010-0116 EC 75219, Rev 0
Download: ML102871019 (183)

Text

PCHG-DESG Engineering Change 0000075219RO REACTOR BUILDING DELAMINATION REPAIR-PHASE 3 CONCRETE REMOVAL i

Aaron Mallner I~~

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No Brown Text Insert 11x8.5 Insert 11x17 Protect Docs Unprotect Docs Lock Controls A.1 EC Folder Contents AOO 0

Contents doom A.1 EC Folder Contents 1

5 A.2 List of Hard Copy Only Pages 3

5 A.3 Revision Summary 3

5 A.4 Problem Statement 3

5 A.5 Solution Statement 3

5 A.6 Operating Experience 4

5 BOO 0

Design docx B.1 Design Specification 1

24 B.2 Scope Description 1

24 B.3 References 1

24 B.4 Design Inputs 4

24 B.5 Assumptions 11 24 B.6 Evaluation 11 24 B.7 Interfaces 23 24 B.8 Quality Class Determination 23 24 COo 0

Mark-up docx C.1 Document/Drawing and Equipment Database 1

2 C.2 Updates of Controlled Documents/Drawings 1

2 C.3 Other Required Updates 1

2 C.4 Equipment Parameter Notes 2

2 C.5 Equipment Document References 2

2 DOO 0

Install docx D.1 Installation Package 1

7 D.2 Installation Requirements 1

7 D.3 Label Requests 6

7 D.4 EC Parts List 7

7 EDO 0

Testing docx E.1 Testing Requirements 1

1 FOO 0

Turnover docx F.1 Turnover/Closeout Summary 1

1 GOD 0

Sketch docx G.1 Installation Sketches 1

1 G01 0

pdf SK-75219-Co01 1

1 HOD 0

Reviews docx H.1 Risk Management 1

25 H.2 Validation Plan 4

25 H.3 Reviewer Comments 5

25 100 0

DV docx 1.1 Design Verification 1

7 J00 0

Checklis docx J.1 Engineering Pre-Job Briefing 1

8 J.2 Engineering Change Checklist 3

8 ZOO 0

Attachme pdf Attachment A - ICRI TechGuide re surface prep 03732 1

43 Zol 0

pdf Attachment B - ICRI 03730 20080806 1

7 Z02 0

pdf Attachment C - ASTM D4580 Sounding -

1 4

Z03 0

pdf Attachment D - ACI 503R 1

28 Z04 0

docx Attachment E - Bond Testing Data Sheet 1

1 Z05 0

docx Attachment F - Intentionally Left Blank 1

1 AOO Contents Page 1 of 5

PCHG-DESG Engineering Change 0000075219RO AOO Contents Page 2 of 5

PCHG-DESG Engineering Change 0000075219RO A.2 List of Hard Copy Only Pages Section/Pages which have blank page place holders for hard copy only originals: None A.3 Revision Summary Original Revision.

A.4 Problem Statement Per AR 358724358724 during the hydro-demolition of the Reactor Building Containment Wall in preparation for Steam Generator Replacement, gaps were exposed between adjacent hoop (i.e.

horizontal) tendons within the boundaries of the temporary access opening. The gaps are generally in a vertical plane between the tendon sleeves and extend for an indeterminate length. This engineering change is part of an overall strategy that will evaluate and accept methods for returning the Reactor Building Containment Wall to its original design base configuration.

A.5 Solution Statement The goal of this EC and interfacing ECs is to ensure the final configuration of the Reactor Building Containment Wall is as good as the original design base configuration. Final analysis of the structure will be based on a new Finite Element model being developed by MPR Associates, Inc.

The repaired wall shall be able to withstand all applicable design conditions, normal and accident.

This EC is the third phase in a multi-phased approach to perform these repairs as follows.

1) Crack Arrest (EC 75000) - A series of cuts will be provided into the delaminated concrete.

These cuts will provide a path of stress relief during the detensioning process. Two horizontal cuts will be made, one above and one below, the steam generator replacement opening. The length of the cuts will not exceed the area of construction opening. In addition to horizontal cuts, vertical cuts will also be installed above and below the contstruction opening at Azimuth 1500. The cuts will run between the currently detensioned vertical tendons at a depth only to cut embedded rebar. This is to minimize cutting active hoop tendons which exist above and below the current containment opening.

2) Detensioning (EC 75218) - A Finite Element model developed by MPR Associates, Inc.

shall be completed to show the necessary detensioning and re-tensioning sequence as well as compliance with the appropriate bases. The detensioning implemented by this phase will ensure adequate prestress can be returned to the Reactor Building structure.

3) Concrete Removal (EC 75219) - This EC will address the removal of the existing delaminated concrete. Method will include a combination of hydro demolition as well as mechanical removal/saw cutting methods. Contract vendor SGT will be providing the implementation of the removal. This EC shall also review the depth of removal, rebar removal requirements, and necessary work platforms associated to perform the work.

Consideration shall be given to any stabilization required to support the delaminated concrete during removal activities.

AOO Contents Page 3 of 5

PCHG-DESG Engineering Change 0000075219RO

4) Concrete Placement (EC 75220) - This EC will address the replacement of the delaminated concrete with new concrete. Mix and installation shall consider criteria evaluated per EC 63016 to originally restore the containment opening. Critical concrete characteristics such as creep, aggregate type, testing requirements, etc. shall also be considered as a part of this phase.

5) Re-tensioning (EC 75221) - This EC will address the final re-tensioning sequence to restore prestress back into the concrete containment shell once the replaced concrete has adequately cured. Final MPR FE analysis results shall be incorporated to ensure the applicable design and licensing bases requirements have been met.

A.6 Operating Experience A search for Hydrodemolition and Concrete Removal under Operating Experience at INPO's website yielded the following items of interest to this EC:

OE 14720- Davis-Besse - Hydrodemolition - Safety Concern:

==

Description:==

A Contract Worker was stationed in the annulus area between the containment vessel and the concrete shield building and was present to monitor any leakage into the annulus. The Contract Worker was installing a sump pump behind the backstop in the Auxiliary Building Annulus Wall when the hydrodemolition commenced operations. The noise

& water from the hydrodemolition.startled the Contract Worker. He dove to the scaffolding decking and, crawled to the ladder. The Contract Worker injured both knees during this action. Radio communication had been established to inform all personnel involved when the machine was to start. This communication did not occur to prepare the worker in the annulus. As other utilities may consider using the hydrodemolition process, it is essential for personnel safety to have a rigid protocol of effective communications.

Causes: There were two causes that contributed to this event. The worker was new to the project and was not aware of what to expect in regards to noise level and slight water intrusion. Primarily however, the supervisor failed to contact the worker in the annulus prior to the hydrodemolition starting. The supervisor, having been involved for several days of hydrodemolition prior to the specific date of the incident, became lax in attention to detail.

How the issue is addressed by this EC:

A note will be added in the precautions and limitations section of the Installation Instructions that the containment coordinator is to be informed prior to starting the hydrodemolition machine. The coordinator must then inform all personnel in the immediate area of the opening that hydrodemolition activities are about to start and noise levels will increase dramatically.

OE 29756 - LaSalle - Hydrodemolition Hose Rupture

==

Description:==

During hydrolazing of a floor drain header in the reactor building on 08/27/09, the pressure regulating valve return hose to the water reservoir tank ruptured at a local fitting. Water is routed through the return hose when the trigger on the wand is released. MC (clean and cycle condensate) water accumulated on hydrolazer skid for approximately 15 seconds until power to hydrolazer was secured. An RP (radiation protection) technician was on the scene when leak occurred and the spill was immediately cleaned up without further incident. No injuries to personnel occurred.

AOO Contents Page 4 of 5

PCHG-DESG Engineering Change 0000075219RO Causes: Lack of a preventive maintenance program for the hydrolazer. The hydrolazer recirculation hose failed due to aging.

How the issue is addressed by this EC: While this OE most likely relates to hand operated hydrolazer, the maintenance implication still applies to any hydrodemolition equipment. A note will be added in the precautions and limitations section of the Installation Instructions that the hydrodemolition equipment is properly inspected prior to use.

OE 14942 - Wolf Creek - Concrete Cutting

==

Description:==

As described in OE 14942, used concrete saw blades may develop cracks over time/usage. Continual usage of the crack blades can cause catastrophic failure and project shrapnel that may cause severe injury to personnel.

Causes: Lack of inspection of saw blades prior to their usage in the field.

How the issue is addressed by this EC: All concrete cutting saw blades shall be thoroughly inspected prior to use to prevent a similar event. Additionally, any activities which cut/bore into the CR3 containment structure have the potential to irreversibly damage the underlying post-tensioning system. As noted in NCR 364655, potential tendon damage occurred during core boring activities associated with condition assessment. As such consideration should be given to this NCR during pre-job briefing activities prior to commencing any work in the field.

Lesson Learned - EC 63016 - OTSG Replacement NCR 358636, Storm Drain Cover Removed - A storm drain cover was removed from a storm drain on the southwest corner of the berm. Some wasterwater resulting from hydrodemolition activities that was pooled up over the storm drain was released. Only Qualified or designated personnel are allowed to remove storm drain covers.

NCR 358653, Hydrodemolition Waste Water Release to Intake Canal - During Hydrodemolition activity at 0500, wastewater discharge became plugged with concrete debris which cause the chute to back up and allow water to Overflow onto the southwest bermed area. Water flowed to a nearby storm crain which was covered with a protective mat which was placed there for oil spill prevention measures. Water pooled up around the storm drain and a worker in the area lifted the mat which allowed approximately 500 gallons of this wastewater to enter the storm drain. The storm drain is connected to an outfall at the CR3 intake canal. Verbal and written notification of release was made to PEF environmental services. A call was then made by EHSS to the FDEP southwest district office at 0955. Contractor was instructed to place a small sump pump in the area of the storm drain to prevent on-going pooling of water in the area. The water was pumped to a drum which was then pumped to the hydrodemolition catch basin.

AOO Contents Page 5 of 5

PCHG-DESG Engineering Change 0000075219RO B.1 Design Specification The details of the design change are specified below:

B.2 Scope Description This EC is the third phase in a series of five ECs in development for the repair of the CR3 RB Containment building delamination.

To facilitate the repair of the CR3 Reactor Building containment delaminated concrete removal will occur between RB Buttresses #3 and #4 located at the 1200 and 1800 azimuths. Removal of concrete will occur during plant no mode. Tendons will be detensioned as prescribed by EC 75218 prior to the removal of the concrete.

Removal of the delaminated concrete will require the removal of the rebar within the boundaries of the delaminated region. Rebar shall be discarded. Sufficient rebar will remain to allow for splicing of the original near face reinforcement and/or additional reinforcement required for final replacement concrete strength as required by interfacing EC 75220.

Based on requirements of the interfacing EC 75220, depth of removal and surface preparation requirements shall also be specified by this EC. The design evaluation will consider both cut and hydrodemolition removal methods.

B.3 References

1. Industry Standards:

1.1.

ASME Boiler and Pressure Vessel Code,Section XI, Subsection IWA, IWE, and IWL of the 2001 edition through the 2003 Addenda, as amended by 10CFR50.55a.

1.2.

ASME Boiler and Pressure Vessel Code,Section III, Division 2, Code for Concrete Containments, 2001 edition through the 2003 Addenda 1.3.

ANSI N45.2.11-1974, Quality Assurance Requirements for the Design of Nuclear Power Plants 1.4.

ASME Boiler & Pressure Vessel Code,Section VIII, Unfired Pressure Vessels, 1965 Ed 1.5.

ASME Boiler & Pressure Vessel Code,Section III, Nuclear Vessels, 1965 Ed 1.6.

ASME Boiler and Pressure Vessel Code,Section III, Division 2, Appendix F, Rules for Evaluation of Service Loadings with Level D Service Limits, 1995 Ed 1.7.

ASME Boiler and Pressure Vessel Code,Section III, Division 1, Subsection NE, 1995 Ed 1.8.

ICRI 03730 (#310.1 R), "Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Corrosion" (Note: ACI 515.1R referenced in this document has been withdrawn on 1/1/1979) 1.9.

ICRI 03732 (#310.2), "Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays" 1.10.

ICRI 03737 (#310.3), "Guide for the Preparation of Concrete Surface for Repair Using Hydrodemolition Methods" 1.11.

ICRI 03739 (#210.3), "Guide for Using In-Situ Tensile Pull-Off Tests to Evaluate Bond of Concrete Surface Materials" 1.12.

ASTM D4580, "Standard Practice for Measuring Delaminations in Concrete Bridge Decks by Sounding" 1.13.

ACI 503R, "Use of Epoxy Compounds with Concrete" 1.14.

ACI 546R, "Concrete Repair Guide" 1.15.

ACI/ICRI Concrete Repair Manual, Third Edition, Volume 1 BOO Design Page 1 of 24

PCHG-DESG Engineering Change 0000075219RO 1.16.

ACI 318-63, "Building Code Requirements for Reinforced Concrete" 1.17.

ASTM A421-65/98a, "Standard Specification for Uncoated Stress-Relieved Steel Wire for Prestressed Concrete"

2. Design Basis Documents:

2.1.

DBD11, Design Basis Document for the Containment, Revision 7 (Tab 1/1) 2.2.

DBD13, Design Basis Document for Major Class I Structures, Revision 5 (Tab 1/3)

3. Specifications:

3.1.

SP-5209, Revision 0, CR-3 Seismic Qualification 3.2.

RO 3040, Requirement Outline, Pre-stressing System Tendon Conduit, Date 06/12/1970 3.3.

SP-5583, Dated 09/18/1968, Specification, Tendon and Associated Conduit, RB 3.4.

GAI Specification SP-5844, Dated 10/21/1970, Specification, Installation of Pre-stressing System Tendon Conduit and Embedded anchorage 3.5.

GAI Specification SP-5646, Fabrication and Delivery of Reinforcing Steel, Dated 04/25/1969 3.6.

GAI Specification SP-5566, RB Liner and Penetrations and Personnel Access Locks, Dated 3/18/1981 3.7.

CR3-C-0003, Rev. 5, "Concrete Work for Restoration of the SGR Opening in the Containment Shell"

4. Drawinqs:

4.1.

421-043, Revision 7, RB Equipment Access Shield Structure 4.2.

421-031, Revision 4, RB Exterior Wall - Concrete Outline 4.3.

421-032, Revision 8, RB Stretch-Out of Exterior Wall Buttress #2, #3, #4 and #5 4.4.

421-033, Revision 8, RB Stretch-Out of Exterior Wall Buttress #5, #6, #1 and #2 4.5.

421-036, Revision 10, RB Exterior Wall - Sections and Details 4.6.

421-039, Revision 5, RB Exterior Wall - Equipment Access Opening Reinforcement Details 4.7.

421-041, Revision 5, RB Ring Girder - Concrete Outline - Plan And Sections 4.8.

421-001, Revision 4, RB Tendon Access Gallery-Plan, Sections and Details 4.9.

Prescon Drawings Series 5EX7-003, (CR3 Dwg Key #S-26 series and S1542'thru S1596)

5. Calculations:

5.1.

189-0013, Revision 8, "Containment Air Temperature Loop Accuracy" 5.2.

S10-0001, Revision 0, "Tendon Tension Calculation" 5.3.

S10-0002, Revision 0, "Finite Element Model Description" 5.4.

S10-0003, Revision 0, "Conduit Local Stress Analysis" 5.5.

S10-0004, Revision 0, "Detensioning" 5.6.

S10-0005, Revision 0, "Bending Tension Interaction Diagrams for Selected Sections" 5.7.

S10-0006, Revision 0, "Seismic, Wind, and Tornado Evaluation and Delamination Depth Evaluation for Detensioned State"

6. Nuclear Generating Group (NGG) Procedures:

6.1.

EGR-NGGC-0003, Rev. 10, "Design Review Requirements" 6.2.

EGR-NGGC-0005, Rev. 29, "Engineering Change" 6.3.

EGR-NGGC-0011, Rev. 13, "Engineering Product Quality" 6.4.

EGR-NGGC-0154, Rev. 5, "Single Failure Analysis" BOO Design Page 2 of 24

PCHG-DESG Engineering Change 0000075219RO 6.5.

EGR-NGGC-0204, Rev. 6, "Evaluation and Selection of Material for Plant Components" 6.6.

MNT-NGGC-0004, Rev. 11, "Scaffolding Control" 6.7.

EGR-NGGC-0015, Rev. 3, "Containment Inspection Program" 6.8.

FIR-NGGC-0003, Rev. 4, "Hot Work Permit" 6.9.

CHE-NGGC-0045, Rev.14, "NGG Chemical Control Program"

7. Plant Procedures:

7.1.

AI-1803, Revision 21, "Safety Standards for Ladders & Scaffolds" 7.2.

SP-178, Revision 30, "Containment Leakage Test - Type 'A' Including Liner Plate" 7.3.

Al-1000, Revision 42, "Housekeeping/Material Condition Program" 7.4.

AI-2200, Revision 13, Guidelines for Handling, Use, and Control of Transient Combustibles 7.5.

SP-300, Revision 219, "Operating Daily Surveillance Log" 7.6.

ISIIWE, Rev 3, "Inservice Inspection Program/Containment Inspection Program -

IWE/IWL" 7.7.

SP-736K, Rev. 0, "Reactor Building Hydrodemolition Release to the Settling Ponds" 7.8.

OP-417, Rev. 111, "Containment Operating Procedure" 7.9.

AI-1820, Rev. 3, "Hazardous and Non-Hazardous Waste Management" 7.10.

A1-1816, Rev. 3, "Industrial Safety Signs and Tags"

8. Plant Change Documents:

8.1.

EC 63016, Revision 31, "Containment Opening" 8.2.

EC 74801, Revision 8, "Containment Structure - Extent of Condition Core Bores" 8.3.

EC 75000, Revision 0, "CR3 Containment Delamination Repair, Phase 1 Crack Arrest" 8.4.

EC 75218, Revision 0, "Reactor Building Delamination Repair Phase 2 - Detensioning (In Development) 8.5.

EC 75220, Revision 0, "Reactor Building Delamination Repair Phase 4 - Concrete Placement (In Development) 8.6.

EC 75221, Revision 0, "Reactor Building Delamination Repair Phase 5 - Retension/Test (In Development) 8.7.

EC 63020, Revision 9, "SG replacement - Outside Erection Crane and Inside Auxiliary Crane" 8.8.

EC 75497, Revision 0, "Containment Delamination Electrical Interference Removal" 8.9.

EC 59400, Revision 0, "Identify the Source and Limitations for CRS Water Supply and Discharge for OTSG Outage RFO-16" 8.10.

EC 63022, Revision 31, "Steam Generator Rigging and Transport" 8.11.

EC 63021, Revision 11, "Temporary Material and Personnel Hoist Outside RB" 8.12.

EC 70377, Revision 1, "Temporary Power outside the RB for SGR Project and Containment Repair"

9. Requlatory Documents:

9.1.

FSAR, Revision 31.3 9.2.

Improved Technical Specifications (Through Amendment 239 and Improved Technical Specifications Bases Revision 81)

10. Other

References:

10.1.

AR 00358724, Exposed Cracks During Hydro-Demolition 10.2.

AR 00372472, 50.59 Screen for EC 75219 10.3.

AR 00370853, Small Cracks Found Parallel to Liner BOO Design Page 3 of 24

PCHG-DESG Engineering Change 0000075219RO 10.4.

AR 00358636, Storm Drain Cover Removed 10.5.

AR 00358653, Hydrodcemolition Wastewater Release to Intake Canal 10.6.

SAF-SUBS-00029, Rev. 3, "General Machine Guarding" 10.7.

SAF-SUBS-00030, Rev. 3, "Hand and Power Tool Safety" 10.8.

SAF-NGGC-2172, Rev. 12, "Industrial Safety" 10.9.

EVC-CRNF-00002, "Crystal River Nuclear Plant Site-Specific Environmental Policies, Permits, Registrations, Certifications, and Plans" 10.10. State of Florida, Industrial Wastewater Facility Permit Number FLA16960, Crystal River Energy Complex 10.11. EVC-SUBS-00008, Rev. 5, "DOT Hazardous Materials" 10.12. EVC-SUBS-00016, Rev. 8, "Hazardous Waste Management" B.4 Design Inputs Following is a list of applicable design inputs specified to meet the requirements of ANSI N45.2.1 1.

1. Basic Functions of Each Structure, System and Component:

Reactor Building Containment Structure:

The containment is a Class I Structure as described in the FSAR Sections 5.1.1.1 and 5.2.1 and the Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1). The primary function of the reactor containment building and its steel liner is to house the primary nuclear system and to provide biological shielding from the fission products that could become airborne under accident conditions. Its failure could result in the uncontrolled release of radioactivity and its integrity is vital for the safe shutdown and isolation of the reactor.

Containment integrity is required in Modes 1, 2, 3, and 4, Ref. 9.5 (TS 3.6). There are no Improved Technical Specification (ITS) Limiting Conditions for Operation (LCOs) for containment integrity during Modes 5, 6 and defueled (TS 3.6.1). The installation of this EC shall occur during No Mode. During No Mode there are no TS requirements for containment integrity or TS Actions that require containment closure, however the containment should not have catastrophic failure during the applicable design basis loads Basis:

Design Basis Document for the Containment (Ref. 2.1, Tab 1/1),

ITS Sections 3.6 and 3.9, FSAR Sections 5.1 and 5.2

2. Performance Requirements such as Capacity, Rating, and System Output:

The reactor containment building is a Class I Structure designed as a passive barrier that is required to maintain its structural integrity during a design basis accident and for all normal and accident load cases and load combination. It was designed for an internal pressure of 55 psig and a temperature of 281 degrees F (accident condition); an internal pressure (external pressure drop) of 3 psig during a tornado; and an external pressure (internal pressure drop) of 2.5 psig during normal operation of the plant. Total suction pressure on interior of Containment of -6.0 psig is also considered. Additional consideration was given to BOO Design Page 4 of 24

PCHG-DESG Engineering Change 0000075219RO the dead load, live load, temperature gradients, and effects of penetrations at accident and working conditions.

Basis:

Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1)

FSAR, Section 5.2.1

3. Codes, Standards, and Regulatory Requirements:

The post tensioned, reinforced concrete reactor containment building is designated as a Class I Structure (FSAR Section 5.1.1.1 and Ref. 2.1) and by definition is therefore nuclear safety-related. Its design and construction predated the establishment of a concrete pressure vessel code. The primary design code for the concrete, tendons and steel reinforcement was ACI 318-63, Parts IV-B and Part V. The tendons conformed to the applicable portions of ASTM A421-65 for low relaxation wire (FSAR Section 5.2.2.3.2). The liner plate conformed in all respects to the applicable Sections of ASA N 6.2-1965 "Safety Standard for Design, Fabrication and Maintenance of Steel Containment Structures for Stationary Nuclear Power Reactors".

Basis:

Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1)

FSAR Section 5.1.1

4. Design Conditions such as Pressure, Temperature, Fluid Chemistry and Voltage:

Pressures:

Normal Operation: +1 to -1 psig Accident pressure inside containment resulting from worst case LOCA: 55 psig Accidental RB Spray Actuation: -2.5 psig on interior of containment Total suction pressure (suction on interior of containment: -6.0 psig)

Tornado differential pressure (suction on outside of containment): -3 psig Temperatures:

Operating temperature inside containment: 60 to 1 150F Operating temperature outside containment: 25 to 100°F Accident temperature: 281 OF Note: While the DBD is the document which describes design operating temperature, SP-300 and TS Section 3.6.1 require operating temperatures below 1 150F during Modes 1-4.

Based on SP-300 and Calculation 189-0013, temperatures have routinely exceeded limit as described by the DBD and may approach 1300F.

Basis:

Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1)

FSAR Section 5.2 ITS Sections 3.6 and 3.9 SP-300 Calculation 189-0013 OP-417

5.

Loads such as Seismic, Wind, Thermal, and Dynamic:

Loads to be considered in verifying the structural integrity of the containment building include both forces resulting from natural phenomena such as earthquake, tornado, wind, BOO Design Page 5 of 24

PCHG-DESG Engineering Change 0000075219RO and hurricane in addition to those resulting from design basis accident conditions, material dead and live loads and forces resulting from tendon stressing. Also to be considered are loads associated with the hydrodemolition process and its interaction with the structure itself. Thermal gradients across the exposed unreinforced concrete section due to delamination removal shall also be considered and monitored to maintain acceptable value as outlined in MPR Analyses (CR3 Calc # S10-0001 thru S10-0006).

Basis: Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1),

ACI 318-63, Parts IV-B and Part V S10-0001 thru S10-0006

6.

Environmental Conditions:

Water requirements:

Concrete removal with hydrodemolition will require large amounts of clean water that must be delivered to the hydrodemolition equipment. Water specimens must be obtained to verify baseline chemical and radiological testing of the water prior to the start of any hydrodemolition. This shall be performed by CR3 chemistry. The resulting waste water and concrete debris that are generated must be disposed of in an environmentally acceptable manner.

Waste water disposal requirements:

Samples for radiological testing and analysis shall be taken at the collection bins and tested at the on-site RP/Chemistry laboratory in accordance with existing site procedures.

Discharge of the water and rubble may continue uninterrupted while samples are being tested and analyzed.

The implementation vendor, SGT, is responsible for water delivery and the means of piping it to and from the containment and is outside the scope of this EC. They are also responsible for determining if the settling ponds have adequate storage for expected waste water. CR3 Chemistry will provide testing of necessary samples. Adjustment of pH will be via temporary storage of hydrochloric acid as required.' Water shall not be discharged to the setting ponds until these samples are cleared by Chemistry and RP. On-site tank storage is to be provided as required by Progress Energy. The details for water supply and disposal for concrete removal shall be included and approved per the associated Work Order Task.

Basis: Offsite Dose Calculation Manual Industrial Waste Water Permit (IWWP)

Chemical Control CHE-NGGC-0045 EC 63016

7.

Interface Requirements:

This EC interfaces with the following ECs:

1. EC 63016, Containment Opening

2. EC 74801, Containment Structure - Extent of Condition Core Bores BOO Design Page 6 of 24

PCHG-DESG Engineering Change 0000075219RO

3. EC 75000, CR3 Reactor Building Delamination Repair, Phase 1, Crack Arrest

4. EC 75218, Reactor Building Delamination Repair Phase 2-Detensioning (In Development)

5. EC 75220, Reactor Building Delamination Repair Phase 4 - Concrete Replacement (In Development)

6. EC 75221, Reactor Building Delamination Repair Phase 5 - Retension/Test (In Development)

7. EC 63020, SG replacement - Outside Erection Crane and Inside Auxiliary Crane (for safe load path usage)

8. EC 75497, Containment Delamination Electrical Interference Removal Basis: NCR 358724

8.

Material Requirements:

Not Applicable

9.

Mechanical Requirements:

Tendon Gallery Sumps shall be tagged and protected during the hydrodemolition process to prevent damage to the pumps from laitance/debris that will be transported through the empty tendon sheaths to the gallery.

Basis: EC 63016

10. Structural Requirements:

This EC will provide for the removal of the delaminated concrete in the Reactor Building exterior wall. Tendons shall be removed at the discretion of SGT using ram detensioning, coiled, and have identification clearly attached. Spare tendons should be ordered to replace any tendon that is damaged during hydrodemolition. These spares shall account for those tendons which may be located in a flexible tendon sheath. Remaining tendon sleeves are to be inspected and repaired prior to containment restoration. The final configuration (reduced wall cross-section) shall be evaluated to show the structure meets all applicable design loads as identified in B.4.5 including but not limited to deadweight, thermal, seismic, and hydrodemolition.

Basis:

Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1)

FSAR Sections 5.1 through 5.2 Scope of EC

11. Hydraulic Requirements:

The pumps and associated piping supplied for the hydrodemolition operation must be capable of providing and recovering the water needed for operation of the hydrodemolition equipment.

Basis: Scope of EC

12. Chemistry Requirements:

Water requirements for hydrodemolition:

BOO Design Page 7 of 24

PCHG-DESG Engineering Change 0000075219RO Clean water must be available for any hydrodemolition activities and must be supplied at a rate which meets the equipment requirements. Water specimens must be obtained to verify baseline chemical and radiological testing of the water prior to the start of hydrodemolition.

Waste water requirements:

Waste water from the hydrodemolition process will be tested before discharge to ensure it meets Plant and the State of Florida permit requirements including the Industrial Waste Water Permit (IWWP). Wastewater release shall be in accordance with SP-736K. Refer to Section B.6.6 for an evaluation of the water requirements. The details for water supply and disposal for concrete removal shall be included and approved per the associated Work Order Task.

Basis:

Industrial Waste Water Permit Chemical Control per CHE-NGGC-0045 SP-736K

13. Electrical Requirements:

Conduit running just above the equipment hatch shall be relocated temporarily to allow for complete removal of the delaminated concrete.

Basis:

EC 75497, Scope of this EC

14. Layout and Arrangement Requirements:

The location of removal shall be between Buttresses #3 and #4. Removal shall be such that sufficient rebar ties remain in place so code splice will be developed between the new rebar and the bars in the undisturbed concrete per concrete placement EC 75220. ACI 318 requires a minimum of 7" for cut #8 rebar. Rebar cuts shall consider future splices around horizontal tendon ducts and adjacent rebar (#11 near the equipment hatch, #18 near ring girder, #9 from Buttresses). EC 75220 shall be referenced for rebar replacement requirements prior to making any rebar cuts to ensure the design requirements are not invalidated. Depth and final surface preparation shall be such that placement conditions are optimized.

Basis:

Scope of this EC ACI 318 Dwg. 421-032 Dwg. 421-036 EC 75220

15. Operational Requirements Under Various Conditions:

Removal shall only commence during the no mode condition so as to maintain the plant in a safe condition. Thermal gradients across the remaining unreinforced concrete wall shall be monitored and controlled based on a 7-day average differential to prevent adverse stress levels within the concrete.

Basis: Scope of EC, OP-417, MPR Analyses S10-0001 thru S10-0005, EC 75218 BOO Design Page 8 of 24

PCHG-DESG Engineering Change 0000075219RO

16. Instrument and Control Requirements:

Thermal gradients shall be monitored across the reduced concrete cross-section following removal. This shall be accomplished with remote instrumentation as required.

Basis: S10-0001 thru S10-0006

17. Access and Administrative Control for Plant Security:

Conduit running just above the equipment hatch shall be relocated temporarily to allow for complete removal of the delaminated concrete. This conduit provides power for plant security lighting. Temporary changes shall not adversely impact site security features.

Basis:

EC 75497, Scope of this EC

18. Redundancy, Diversity, and Separation Requirements of Structures, Systems, and Components:

Not Applicable

19. Failure Effects on Requirements of Structures, Systems, and Components:

The primary function of the reactor containment building and its steel liner is to house the primary nuclear system and to provide biological shielding from the fission products that could become airborne under accident conditions. Its failure could result in the uncontrollable release of radioactivity and its integrity is vital for the safe shutdown and isolation of the reactor. Repair of the delamination will occur during no mode operation during which time containment Operability is not required (TS 3.6.1). The partially detensioned containment could possibly pose a threat to the adjacent Auxiliary Building (due to the presence of the spent fuel pools), during a seismic or tornado event (11/I relationship).

Basis:

Improved Technical Specifications 3.6, 3.9 FSAR Section 5.0

20. Test Requirements:

Surface preparation of removed concrete shall be such that new concrete can adequately bond to the existing concrete. Surface preparation testing shall use ACI 503R, Appendix A as a guideline. Additional subsurface testing shall be performed in accordance with ICRI 03739.

Basis:

ACI 503R-93 (Reapproved 2008)

ICRI 03739

21. Accessibility, Maintenance, Repair, and ISI Requirements:

Not Applicable

22. Personnel Requirements and Limitations:

Not Applicable BOO Design Page 9 of 24

PCHG-DESG Engineering Change 0000075219RO

23. Transportability Requirements:

Not Applicable

24. Fire Protection or Resistance Requirements:

Not Applicable

25. Handling, Storage, and Shipping Requirements:

Not Applicable

26. Other Requirements to Prevent Undue Risk to the Health and Safety of the Public:

Safe load paths shall be considered to offset potential load drop scenarios during movement of any required equipment over vital plant components.

Basis:

EC 63020

27. Materials, Processes, Parts, and Equipment Suitability for Application:

Not Applicable

28. Safety Requirements for Preventing Personnel Iniury:

The removal process should utilize properly qualified mobile or suspended platforms and/or scaffolding as required. Hydrodemolition equipment should utilize enclosures which are capable of capturing all loose debris (i.e. high strength netting) in order to prevent falling objects on personnel or plant equipment below.

The project safety interface should ensure that proper and sufficient consideration is made of the requirements for fall protection and of the dangers involved in working at heights.

Pre-Job briefs shall incorporate any relevant OE prior to commencing work in the field.

Consideration should be given the dangers associated with utilizing concrete cutting equipment.

Basis:

OSHA requirements SAF-NGGC-2172, "Industrial Safety" or SGT Equal Al-1 803, "Safety Standards for Ladders & Scaffolds" OE 14942, "Circular Concrete Saw Blade Cracking May Cause Personnel Injury"

29. (CR3) Circuits for systems with Improved Technical Specifications testing requirements:

Not Applicable

30. (CR3) Emergency Diesel Generator Loading Impact Assessment:

Not Applicable BOO Design Page 10 of 24

PCHG-DESG Engineering Change 0000075219RO B.5 Assumptions None B.6 Evaluation

1. Basic Functions of Each Structure, System and Component:

Reactor Building Containment Structure:

The CR3 Reactor Building is similar in design to the containment buildings for the Three Mile Island Nuclear Station Unit 1, the Turkey Point Plant, the Palisades Plant, the Point Beach Plant, and the Oconee Nuclear Station.

The containment is a concrete structure with a cylindrical wall, a flat foundation mat, and a shallow dome roof. The foundation slab is reinforced with conventional mild-steel reinforcing. The cylinder wall is prestressed with a post-tensioning system in the vertical and horizontal directions. The dome roof is prestressed utilizing a three-way post-tensioning system. The inside surface of the reactor building is lined with a carbon steel liner to ensure a high degree of leak tightness during operating and accident conditions. Nominal liner plate thickness is 3/8 inch for the cylinder and dome and 1/4 inch for the base.

The foundation mat is bearing on competent bearing material and is 12-1/2 feet thick with a 2 feet thick concrete slab above the bottom liner plate. The cylinder portion has an inside diameter of 130 feet, wall thickness of 3 feet 6 inches, and a height of 157 feet from the top of the foundation mat to the spring line. The shallow dome roof has a large radius of 110 feet, a transition radius of 20 feet 6 inches, and a thickness of 3 feet. The containment has been designed to limit the leakage rate to 0.25% by weight of contained atmosphere in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at the design pressure and temperature.

Per Section 5.2 of the FSAR and Ref. 2.1 the design of the containment building is based on:

" The containment of radioactive material which might be released from the reactor core following a Design Basis Loss-Of-Coolant-Accident (LOCA).

" Temperature and pressure generated from the LOCA, i.e. 281 degrees F and 55 psig.

(The design pressure is 55 psig but the DBA pressure is 54.2 psig (Ref. FSAR Section 14.2.2.5.9 and TS B 3.6.1).

Operational and Safe Shutdown Earthquakes Severe weather phenomena, i.e. hurricane winds, tornado and tornado missile The post-tensioned, reinforced concrete containment building was designed by the ultimate strength methods in accordance with ACI 318-63, Part IV-B and Part V, Chapter 26 "Prestressed Concrete". The load capacity of members was reduced by a capacity reduction factor 0=0.90 for flexure in accordance with Section 1504 of ACI 318-63 (FSAR Section 5.2.3.3.1).

Based on the no mode state of the plant during the removal of delaminated concrete, the normal design base requirements do not apply. The delaminated region will be removed and BOO Design Page 11 of 24

PCHG-DESG Engineering Change 0000075219RO repaired prior to final start-up, as such, the Reactor Building containment is not adversely affected.

2.

Performance Requirements such as Capacity, Rating, and System Output:

Since the reactor containment building acts as a passive barrier, it must be verified for all applicable Design Basis loads and load combinations, including all loads resulting from any necessary repair activities, to ensure its structural integrity during restoration and through end of plant life. Its failure could result in the uncontrollable release of radioactivity and its integrity is vital for the safe shutdown and isolation of the reactor. Since the containment is essentially returned to its original configuration after all phases of repair, there will be no changes to any performance requirement for capacity, rating or system output.

The delaminated concrete removal scope does not adversely impact the performance requirements of the current state of the Reactor Building containment in terms of the total repair methodology to restore design base function. This process will be credited as a repair aid only to allow new concrete placement and retensioning activities as described in EC 75220 and 75221, respectively. Refer to Sections B.6.5 and B.6.10 for review of concrete removal process.

3. Codes, Standards, and Regulatory Reguirements:

At the completion of all repair activities, the post tensioned, reinforced concrete containment building will comply with all applicable design basis loads, load combinations, codes and standards. Final Finite Element Model analysis will ensure the containment maintains this requirement before being returned to service.

4. Desigqn Conditions such as Pressure, Temperature, Fluid Chemistry and Voltage:

Removal of the delaminated region of the containment building wall will not change any of the design conditions for containment. The extent of repairs of all 5 interfacing ECs is to ensure the final configuration of the containment meets its original design base requirements.' Concrete removal is being credited only for preparing the degraded regidn for the final design repair only. As such, the removal is merely an aid in restoring the containment to its intended configuration.

5.

Loads such as Seismic, Wind, Thermal, and Dynamic:

The purpose of this EC is to remove the delaminated concrete in the CR3 RB containment as identified in NCR 358724. This delaminated region is located between buttresses #3 and

1. 4 in a relatively symmetric hourglass shape surrounding the SGR construction opening created by EC 63016. The depth of the delamination varies from a few inches to an observed 11 " as shown on SK-72519-COO1. Removal of all unsound concrete is the only feasible method to ultimately restore the containment structure back to its design base condition.

Historically delamination had occurred during initial construction of the plant within a large portion of the containment dome. Similar to this EC, the delaminated region was removed via mechanical means, the surface prepared, radial rebar installed, and the concrete replaced. The latter portion of the repair approach shall be addressed in interfacing EC BOO Design Page 12 of 24

PCHG-DESG Engineering Change 0000075219RO 75220. This evaluation will focus primarily on the removal shape, the method of removal, surface preparation, and the interim condition of the containment structure prior to concrete replacement.

Both the American Concrete Institute and the International Concrete Repair Institute provide methods and guidelines for repairing degraded concrete structures. A review of ICRI 03730, Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion (Attachment Z01), shows that the basic shape for any removal should encompass any area of delamination in the most basic, rectangular shape possible.

Additional consideration should be given to all edges ensuring they are straight, square, and free of feathered edges. Based on the above, a stepped approach will be utilized as shown on SK-72519-C001 to remove the delamination. Only rectangular type joints will be utilized during removal to meet the ICRI guidelines. The depth of the removal is dictated by both existing MPR finite element analyses S10-0001 thru S10-0005 and ACI 318 code requirements for clear distance behind newly placed reinforcement. The analyses assume a uniform delamination between buttresses #3 and #4 of an average of 10". To prevent invalidation of this analysis, the typical removal depth shall be 10" (the centerline of the hoop tendons). It is understood that localized areas may need to be removed deeper than the 10" as the delamination extends deeper in some areas, particularly above the construction opening. To ensure the average of 10" used in the MPR analyses is not invalidated, localized areas exceeded the 10" were examined and deemed acceptable for the purpose of this removal EC (Reference S10-0006). Based on AREVA design engineering input, ACI 318 code requirements dictate that a minimum of 81/2" of delamination be removed to provide adequate bond development length for the proposed radial reinforcement ties being installed per EC 75220. The 10" removal depth bounds this requirement. To minimize a slight stepping approach, removal will allow a typical 10" of removal with localized areas exceeding slightly further.

Further review of ACI and ICRI documents reveals methods most associated with concrete removal. It should be noted that concrete removal directly impacts surface preparation techniques. Methods described by these documents include grinding, abrasive blasting, water jetting, milling, scarifying, needle scaling, and flame blasting. Based on previous installer work experience, hydrodemolition provides the fastest, most uniform method of removal. ICRI 03732 (Attachment ZOO), Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays, describes a series of recommended surface profile finishes as well as methods to attain those finishes.

Furthermore ICRI 03737, Guide for the Preparation of Concrete Surfaces for Repair Using Hydrodemolition Methods, describes the expected surface profile as a result of hydrodemolition removal. Based on both ICRI 03732 and ICRI 03737, a surface profile of at least CSP-6 could be expected but can approach CSP-9, levels which provide a good level of surface irregularity ideal for creating a mechanical bond. Based on ICRI 03732, only water jetting, milling, flame blasting, needle scaling, and scabbling provide surface profiles suitable to concrete replacement. It should be noted that mechanical impact methods have the highest tendency to create micro-cracking within the concrete surface. Therefore, based on the guidelines produced by ICRI, hydrodemolition is the preferred acceptable method for concrete removal. Further localized removal may occur with manual hydrodemolition or less invasive mechanical methods as described in ICRI 03732 and ICRI 03730. An exception should be noted that only hydrodemolition and saw cutting shall be permitted in the edge areas. This is to ensure no feathered edges occur at these critical construction joints.

BOO Design Page 13 of 24

PCHG-DESG Engineering Change 0000075219RO Once the majority of concrete has been removed and after ensuring that sound concrete exists beyond the removed concrete final surface finishing can commence. Guidelines require surfaces to be cleaned and free of loose aggregate. Particular attention is required for hydrodemolition as the removed slurry can harden on the concrete surface and interfere with creating an adequate mechanical bond. Consistent with ACI 546R, Concrete Repair Guide, and ACI 503R (Appendix A, Attachment Z03), Use of Epoxy Compounds with Concrete, a simplified field test for surface soundness will be implemented to ensure the surface is adequately prepared for the placement of new concrete. A small aluminum t-bar will be affixed to the concrete surface with epoxy and pulled off. The pull off force will be recorded via a dynamometer and compared to the design base document tensile stress value of 200 psi. This will ensure that any portion of the concrete is just as likely to crack as the newly formed bond. Frequency of the testing will be performed as per those guidelines per ACI 503R at the rate of 1 test per every 100 ft2 of prepared concrete surface. Should testing consistently show adequate preparation, the frequency of testing may be reduced at the discretion of the responsible civil engineer. It should be noted that radial rebar will be installed as part of the EC 75220 scope that alone will be capable of withstanding design stress across the repair interface; however, concrete preparation as outlined above will ensure that complete reliance on this radial rebar is minimized. To further ensure all delamination has been removed, concrete sounding techniques as described in ASTM D4580 (Attachment Z02) will ensure proper consideration is given to driving out all areas of loose concrete.

It should be noted that the root cause has not yet fully refuted the hydrodemolition process with respect to the creation of subsurface micro-cracking and induced vibrations in the concrete surface. However, surface preparation requirements dictate only a few methods will create the surface required for new concrete placement. Based on best industry practices hydrodemolition is the most highly-recommended for both removal and surface preparation. Other alternate methods which would provide the required surface profile such as shotblasting or scarifying have a higher tendency to create surface and subsurface micro-cracking.

Therefore, in order to minimize the likelihood of micro-cracking, hydrodemolition is the most feasible method of removal as noted above. To ensure significant damage has not been sustained in the structure, in-situ pullout testing of the subsurface will show the necessary strength remains in the concrete subsurface. This testing will be in accordance with ICRI 03739 (Attachment Z07). This requires a core to be drilled and a metal disc affixed to the top of the core. The core is then pulled similarly as outlined above and the tensile stress recorded. While the primary intent of this test is to ensure a good bond between adjacent materials, it can also show whether or not micro-cracking has been created to the extent which allow additional delamination to propagate through the sound concrete sub-surface. The acceptance criteria would also be 200 psi as outlined above. Per the ICRI recommendations testing should occur at a frequency of 3 per 5000 ft2 of repair area. The devised pullout testing rig used for examining adequacy of the surface prep may be adjusted for this similar usage. The above testing techniques and adherence to the guidelines of the ACI/ICRI repair guidelines will ensure minimal adverse impact will occur to the containment structure. Additionally, the use of hydrodemolition may or may not induce vibrations through the delaminated surface which are capable of propagating the crack further into buttresses #3 and #4. To mitigate this risk as much as possible, a saw cut will be placed around the general removal area before hydrodemolition commences. This cut line will be offset 6" from the buttresses and top of the equipment hatch doghouse haunch. The cut will be a minimum of 11/2" or as deep as reasonable achievable to as to prevent the cutting of underlying rebar. This cut will allow a weakened path for any potential propagation while minimizing the likelihood of propagation into the BOO Design Page 14 of 24

PCHG-DESG Engineering Change 0000075219RO buttresses or equipment hatch concrete. Any further required removal would be limited to less invasive hand chipping techniques as required. It should be noted that possible strategies were discussed with Root Cause team in order to alleviate some of the concerns regarding micro-cracking/crack propagation; however, the available condition assessment data and experience dictated this design as the best approach and the risk of potential crack propagation was accepted and mitigated as best as reasonable achievable. Furthermore, the intent of this EC is based on best, sound engineering judgment with industry guidance to minimize the likelihood of crack propagating into the buttresses, equipment hatch, and ring girder concrete.

Based on the previous usage of hydrodemolition during the creation of the construction opening, the water jets will impart a load on the reactor building containment wall.

Communication with the OTSG replacement Responsible Engineer indicates that these loads are minor based on industry guidelines, on the order of 500 lbs in a localized area.

When comparing those loads with the magnitude of the deadweight of the affected critical section as well as the design wind loads, it can be seen that the load is bounded and well within the design strength of the structure. It should be noted, however, that the Delamination Root Cause Evaluation team is examining specific failure modes associated with the hydrodemolition itself related to Induced Vibration, excessive jet pressure, excessive blasting rate, and fine micro-cracking. Those failures modes have yet to be completely refuted and thus hydrodemolition cannot be used without the aforementioned testing criteria to ensure the best achievable concrete preparation is achieved.

MPR analyses S10-0001 thru S10-0006 bound the interim condition of the CR3 RB containment structure in the no mode condition. In the interim condition, the structure is not required to meet design base requirements as the reactor is defueled. The assumption of the 10" loss of wall section will be maintained as described in those analyses so as not to create a condition that is outside the bounds of those calculations. Localized removal areas past 10" will only be allowed at the discretion of the responsible-civil engineer. This is described in the work installation instructions. Load conditions which may have an impact on the containment shell, dome, liner plate and base mat have been accounted for through element self weight in the MPR finite element models and associated ANSYS models as evaluated below.

Wind Loads:

While defueled there are no TS requirements for containment integrity or TS Actions that require containment closure, therefore, design basis wind loads are not applicable. While the containment is defueled and partially detensioned it could possibly pose a Il/I hazard to the adjacent Auxiliary Building due to the presence of the spent fuel pools. However, containment repair will occur prior to the start of hurricane season which normally starts in June, therefore, hurricane wind loads are not evaluated. It should be noted that the tornado wind load analysis bounds the normal and hurricane wind loading scenarios.

Tornado Wind Loads:

While defueled there are no TS requirements for containment integrity or TS Actions that require containment closure. Therefore, design basis requirements for Tornado Load are not applicable. However, while the containment is defueled it could possibly pose a Il/I (collapse) hazard to the adjacent Auxiliary Building due to the presence of the spent fuel pools. Accordingly, calculation S10-0006 has conservatively evaluated the partially detensioned containment shell for design basis tornado wind loads, with the delaminated BOO Design Page 15 of 24

PCHG-DESG Engineering Change 0000075219RO concrete removed, for a tornado wind velocity of 300 mph and an external pressure drop of 3 psig (Ref. 2.1, 5.7 & Section 5.2.1.2.6 of the FSAR)

Seismic Loads:

The appropriate seismic loads have been applied to the containment ANSYS finite element model generated by MPR and evaluated in Calculation S10-0006.

Per the Containment DBD (Ref. 2.1), and Section 5.2.1.2.9 of the FSAR, the design basis seismic parameters are as follows:

Operating Basis Earthquake (OBE) 0.05 g, maximum horizontal ground motion acceleration 0.033, 0.033g, maximum vertical ground motion acceleration Safe Shutdown Earthquake (SSE) 0.1 g, 0.1 g maximum horizontal ground motion acceleration 0.067, 0.067 g, maximum vertical ground motion acceleration While defueled there are no TS requirements for containment integrity or TS Actions that require containment closure. However, while the containment is defueled it could possibly pose a seismic Il/I hazard to the adjacent Auxiliary Building due to the presence of the spent fuel pools. MPR evaluated the effects of seismic loads on the partially detensioned containment shell with the delaminated concrete removed and concluded that the containment shell had sufficient strength to preclude any possible collapse mechanism (Ref.

calculation S10-0006).

Thermal Loads:

As outlined in the MPR analyses, temperature monitoring will have a significant role in the overall stability of the structure in the interim condition. Based on analysis, a thermal gradient differential between the interior and exterior faces of the containment wall could result in stresses that create and/or propagate cracks within the remaining unreinforced concrete cross-section.

The effects of thermal loads on the containment shell While detensioned have been evaluated for the following three items:

" Thermal loads due to restrained expansion of containment liner Axial (average cross-sectional) temperature within the concrete Temperature gradient through the thickness of the concrete sections Temperature inside containment during removal will be controlled by Operations so that the inside temperature does not vary from the outside temperature by more than 100 F.

Operations will use the RB ventilation cooling, heating and purge system per OP-417 making daily adjustments as required to maintain the delta as close to zero as possible based on a 7 day rolling average. Temperature Monitoring Requirements are outlined in B.6.16.

Polar Crane Loads:

The partially detensioned containment shell, with the delaminated concrete removed, has been evaluated by MPR (Refer to Calc. S10-0004) for the dead weight of the polar crane BOO Design Page 16 of 24

PCHG-DESG Engineering Change 0000075219RO only. The polar crane cannot be used for any lifts prior to the completion of analysis as documented in EC 75220.

Pressure Loads:

During No Mode there are no accident pressure loads that need be evaluated.

6.

Environmental Conditions:

Radiation decontamination of the concrete rubble and waste water, and any associated anchorage components may be required before disposal. Discharge of the water and rubble may continue uninterrupted while samples are being tested and analyzed. After the concrete rubble has been released by RP it will be hauled offsite to a landfill.

Implementation vendor, SGT, is responsible for water delivery, storage and the means of piping it to and from the containment and is outside the scope of this EC. They are also responsible for determining if the settling ponds have adequate storage for the expected waste water from hydrodemolition.

The details for water supply and disposal for concrete removal are outside the scope of this EC and will be included and approved per the associated Work Order Task.

Water requirements:.

EC 63016 and ECED 59400 identified the possible source of this water as the well fields located to the east of CR3, operated and maintained by the fossil group at Crystal River South (CRS). Well water could be diverted through existing CRS plant piping or temporary piping to one of the existing abandoned oil storage tanks (Cap. 8,000,000 gallons) which have been successfully used in the past by CRS and CR3 to satisfy requirements for bulk water storage for other high water demand projects. Water from this storage tank could then be pumped either via temporary piping to the hydrodemolition equipment located at the containment.

Water supplied to the hydrodemolition contractor should have total suspended solids of less than 45ppm and must undergo laboratory analysis to baseline radio nuclides and other chemical parameters as determined by RP and the chemistry department. Again, the details for water supply and disposal for concrete removal are outside the scope of this EC and will be included and approved per the associated Work Order Task.

Waste water disposal:

Samples for radiological testing and analysis shall be taken and tested at the on-site RP/Chemistry laboratory in accordance with existing site procedures. Discharge of the water and rubble may continue uninterrupted while samples are being tested and analyzed.

Specific details developed on radiological sampling and analysis of the waste generated during hydrodemolition will be addressed by the associated work package.

As per EC 63016 and communication with the Sr. Environmental Specialist, waste water could be discharged to the south percolation ponds which have been determined (by CR3 and corporate environmental) to be within the current definition of wastewaters under the Plant Industrial Waste Water Permit. Therefore, sending the pre-tested (Refer to B.6.12 for testing requirements) waste water to the ponds is currently allowed. However, no discharge BOO Design Page 17 of 24

PCHG-DESG Engineering Change 0000075219RO shall take place until both site chemistry and RP have cleared samples as acceptable for discharge. Hydrodemoltion may continue provided all the waste is collected in temporary basins or tanks. Refer to ECED 59400 for an evaluation of the risks associated with using the percolating ponds for effluent disposal. The source and storage of supply water, the use of the existing plant piping/facilities, use of the percolating ponds, and the erection/support of tetnporary piping for the disposal of the waste water is outside the scope of this EC and will be addressed by the relevant work orders.

Additionally, based on the previous use of Mac & Mac as outlined in EC 63016, wastewater would need to be treated via a skid mounted treatment facility. The purpose of this facility is to capture suspended material (grease, oil, concrete, etc.) and provide pH adjustment prior to discharge. This facility would require the temporary storage of up to 1600 gallons of 17%

hydrochloric acid. This is acceptable as reviewed in Attachment Z63 of EC 63016 without further review based on its previous usage.

7.

Interface Requirements:

This EC repair will coordinate final design repair with EC 63016, Containment Opening, EC 74801, Containment Structure - Extent of condition Core Bores, EC 75218 - Reactor Building Delamination Repair Phase 2-Detensioning (In Development), EC 75219 -

Reactor Building Delamination Repair Phase 3 - Concrete Removal (In Development), EC 75220 - Reactor Building Delamination Repair Phase 4 - Concrete Placement (In Development), and EC 75221 - Reactor Building Delamination Repair Phase 5 -

Retension/Test (In Development).

Safe load paths shall be considered per EC 63020, particularly when using the Manitowoc 2250 crane. Installation of any hydrodemolition equipment would require strict adherence to the safe load paths as identified in that EC.

8. Material Requirements:

There is no evaluation required for this Design Input.

9. Mechanical Requirements:

During hydrodemolition of the concrete containment wall, water will drain down the exposed vertical tendon sheaths into the tendons gallery where it shall be collected in 55 gallon drums. However, it is expected that considerable overflow could occur (based on previous SGR experience) which will be collected in the tendon gallery sump. Since this waste water contains dissolved concrete (cement, sand and larger aggregate) it must be kept out of the plants waste water system. SGT mechanical workers shall establish sufficient boundaries or barriers that will prevent the concrete waste water from reaching tendon sump. The station gallery sumps, SDP-3A and SDP-3B will remain in normal operation. Sump pumps will be installed inside of the barrier, which will pump the waste water that collects in the sump to the portable water treatment plant located outside the protected area. Prior to the beginning of hydrodemolition activities, steps must be taken to confirm the proper operation and discharge volume of the temporary sump pump they supply. In the unlikely event that some water from the hydro-demolition process leaks past the barriers, it would be processed from the tendon gallery sump to the Turbine Building sump. This water would then be processed out with the normal station release process contained in OP-407N, Liquid Releases from the Secondary Plant. There is no need for additional testing the water that drains into the tendon BOO Design Page 18 of 24

PCHG-DESG Engineering Change 0000075219RO gallery if the gallery is classified as being outside the RCA. If the gallery is classified as being inside the RCA then additional sampling is required by RP.

10. Structural Requirements:

Please reference B.6.5 for formal evaluation of the concrete removal.

11. Hydraulic Requirements:

Based on previous experience, the water requirements for the hydrodemolition activities are approximately 2,000,000 gallons of clean water and must be supplied at the rate of up to 360gpm.

12. Chemistry Requirements:

Water requirements for hydrodemolition:

ECED 59400 identified the possible source of this water (approximately 2,000,000 gallons) as the well fields located to the east of CR3, operated and maintained by the fossil group at Crystal River South (CRS). RP/Chemistry laboratory baseline testing of the water before it is delivered to the hydrodemolition contractor for radio nuclides and other chemical parameters is required to verify that TSS is within the vendor requirements.

Chemical requirements for discharging the waste water are within the scope of this EC and are discussed below under '"Waste Water'. The implementation vendor, SGT, is responsible for water delivery, storage and the means of piping it to and from the containment and is outside the scope of this EC. They are also responsible for determining if the settling ponds have adequate storage for the expected waste water generated from hydrodemolition.

The details for supply and disposal of the water for concrete hydrodemolition will be included and approved per the associated Work Order Task.

Waste water:

Samples for radiological testing and analysis shall be taken and tested at the on-site RP/Chemistry laboratory in accordance with SP-736K. Discharge of the water and rubble may continue uninterrupted while samples are being tested and analyzed.

Per EC 63016, the environmental/chemistry groups evaluated the current requirements of the Plant Industrial Waste Water Permit (IWWP) and concluded that waste water (non-radiological) treatment is required as a pre-requisite before discharging the water. The following waste water (non-radiological) tests will be performed as a pre-requisite for discharge:

Only PH samplinq will need to be performed as a pre-requisite for discharqe.

Contractor should strive to keep the pH between 6.0 and 9.0. Periodic sampling of pH will be needed. A "stop job" limit shall be established at pH less than or equal to 2, or pH greater than or equal to 12.5.

13. Electrical Requirements:

Temporary EC 75497 evaluates the necessary requirements for moving the interfering conduits located directly above the equipment hatch. More specific details concerning the BOO Design Page 19 of 24

PCHG-DESG Engineering Change 0000075219RO temporary layout and/or necessary security compensatory actions will be found within that document. Please reference EC 75497 for additional details. EC 70377 addresses the availability of temporary power for-work associated with the repair ECs.

14. Layout and Arrangement Requirements:

The shape of removal as shown on SK-72519-CO01 is within best industry guidelines for concrete repair. The squared corners and minimization of feathered edges as recommended in ICRI 03730 (Attachment Z01) and ICRI 03737 are incorporated into the repair methodology. Coupled with proper surface preparation techniques and consideration for rebar splices/staggering, the layout will allow for successful concrete placement per EC 75220.

15. Operational Requirements Under Various Conditions:

As stated in the design input, the work shall only commence during shut down conditions.

This is to minimize potential adverse impact to the structure. Thermal gradients requirements and evaluation are as described in B.6.5.

16. Instrument and Control Requirements:

Temperature Monitoring Requirements:

Calculation S10-0004 has included a 100 F thermal gradient in the ANSYS FEM when evaluating the containment shell for reduced prestress and reduced concrete thickness.

The surface temperature of'the liner plate will be measured using thermocouples (As in Attachment Z06 or similar devices that can measure surface temperature) attached to the surface of the liner plate at a minimum of two representative locations. Similar devices will be attached to the inside surface of existing core bores located in the general vicinity of buttresses 3 and 4 as required to obtain representative internal concrete temperatures.

These devices will be placed so that they can measure internal bore surface temperature at 3 approximate depths; 4" inside the core bore, at mid-point and at the base of the core bore or at least 12".

The temperature measuring instruments for the various depths may be combined in a single core bore' or spread among adjacent core bores as determined practical during installation. Once mounted, the core bore should be plugged with at least 2"-3" of insulating material at the outer face. In addition, two thermocouples will record ambient air temperature outside containment. The temperature devices shall be capable of recording temperatures at a sampling frequency of at least once every 10 minutes.

If capability exists, the temperatures will be made available on the CR3 business network for display on OSI Pl.

At a minimum, the rolling 7 day average temperature will be trended and recorded for the inner liner surface and 4" concrete depth (in PI if available). It is desired to have indication from all devices in Pl. The seven day average is listed because of the latent affect that temperature has on a 42" thick (or 32" thick after delaminated concrete is removed) concrete wall.

Thermal measuring devices are not attached to the outside.face of the containment wall since un-conservatively high temperatures would be recorded if the measurements were taken at the surface of the containment wall due to solar radiation, i.e. the surface BOO Design Page 20 of 24

PCHG-DESG Engineering Change 0000075219RO temperature is directly affected by the sun and would not be representative of the average temperature 2"-3" inside the wall (Reference Attachment Z29R0 of EC 75218).

The thermal gradient that will be managed will be the difference between the average of the two thermocouples attached to the liner and the average of the two thermocouples 4 inches from the face of the outside containment wall inside the core bores. Operations will use the RB ventilation cooling, heating and purge system per OP-417 making daily adjustments as required to maintain the delta as close to zero as possible based on a 7 day rolling average.

The limit on the ambient temperature inside containment is 60 degrees. If the delta between the thermocouples inside containment and 4 inches from outside face of containment inside the core bores reaches 8 degrees F, engineering will evaluate if additional actions need to be taken outside containment by SGT to increase the concrete temperature. These actions may include tents, blankets, heaters, and moisture. Based on a review of the stresses in the unreinforced section of concrete during the detensioned condition, the extent of protection outside containment is expected to be limited to an area about 10 feet beyond the perimeter of the steam generator opening.

Summary: Temperature gradient (4 inches subsurface to inner liner) will be managed as close to zero as practical based on a seven day rolling average. When the thermal gradient reaches 8 degrees F, an evaluation will be made by engineering with the intent of determining if forecasted temperatures could result in a sustained temperature gradient greater than 10 degrees F. If such a gradient is judged possible then appropriate actions will be taken. The action is to preclude a temperature gradient of 10 degrees taken as a 7 day rolling average.

17. Access and Administrative Control for Plant Security:

Temporary EC 75497 evaluates the necessary requirements for moving the interfering conduits located directly above the equipment hatch. More specific details concerning the temporary layout and/or necessary security compensatory actions will be found within that document. Please reference EC 75497 for additional details.

18. Redundancy, Diversity, and Separation Requirements of Structures, Systems, and Components:

There is no evaluation required for this Design Input.

19. Failure Effects on Requirements of Structures, Systems, and Components:

The overall concrete removal will not adversely affect the final design base configuration of the Reactor Building Containment. This is due to the fact that the removed condition is not required to be credited for final design loading conditions as the repaired containment would need to meet. Based on the evaluation in B.6.5, the adjacent Auxiliary Building will remain unaffected as a result of the removal and the reduced section is stable for the applicable loading conditions. Subsequent interfacing ECs will restore the containment to meet its design base requirements.

20. Test Requirements:

The surface preparation testing requirements are in line with industry best practice standards. The testing as described in Appendix A of ACI 503R are easy to replicate on a BOO Design Page 21 of 24

PCHG-DESG Engineering Change 0000075219RO large scale and will quickly discriminate between an adequately cleaned and prepared surface and an unacceptable surface for future bonded concrete. Based on its simplicity and its recommendation as a best industry practice, this testing is considered both prudent and acceptable for surface examination prior to concrete placement. Simple subsurface testing per ICRI 03739 will show if micro cracking has developed to a point at which would impact the structure. This testing is minimally invasive and requires only 3 points per 5000 ft2 of repair area. Any other required ASME Section Xl, Subsections IWE/IWL as well as ASME Section III inspections and testing shall be implemented under interfacing ECs 75218, 75220, and 75221.

21. Accessibility, Maintenance, Repair, and ISI Requirements:

There is no evaluation required for this Design Input.

22. Personnel Requirements and Limitations:

There is no evaluation required for this Design Input.

23. Transportability Requirements:

There is no evaluation required for this Design Input.

24. Fire Protection or Resistance Requirements:

There is no evaluation required for this Design Input.

25. Handlin., Storaqe, and Shippinq Requirements:

There is no evaluation required for this Design Input.

26. Other Requirements to Prevent Undue Risk to the Health and Safety of the Public:

Safe load paths as described in EC 63020 shall be considered to minimize the likelihood of damaging critical plaint equipment during any necessary rigging activities. No further evaluation is required for this design input.

27. Materials, Processes, Parts, and Equipment Suitability for Application:

There is no evaluation required for this Design Input.

28. Safety Requirements for Preventinq Personnel Iniury:

The concrete removal process will utilize properly qualified mobile or suspended platforms as used for the tendon activities being performed during Refueling Outage 16 and/or scaffolding as required. The project safety interface must ensure that proper and sufficient consideration is made of the requirements for fall protection and of the dangers involved in working at heights as well as falling objects and dropped items. Future revisions may be used to incorporate any other platform needs as they are determined by the SGT project team.

BOO Design Page 22 of 24

PCHG-DESG Engineering Change 0000075219R0

29. (CR3) Circuits for systems with improved Technical Specifications testing requirements:

There is no evaluation required for this Design Input.

30. (CR3) Emergiency Diesel Generator Loading Impact Assessment:

There is no evaluation required for this Design Input.

B.7 Interfaces Progress Energy EC Proiect Team and Interfaces Aaron Mallner - Responsible Engineer, CR3 Containment Design Base Analysis Team Ron Knott - CR3 Containment Design Base Analysis Team Rick Pepin - CR3 Containment Repair Team Lead Paul Fagan - CR3 Containment Condition Assessment and Engineering Team Lead Charles Williams - CR3 Containment Root Cause Analysis Team Lead C. Glenn Pugh - RE EC 75220 Sid Powell - Licensing Support John Holliday - Contract SGR EC 63016, Containment Opening RE Keith Allen - CR3 Design Superintendent Rick Portmann - CR3 Containment IWE/IWL Program Owner Paul Gosselin, SGT - Planner Glen Maxwell, Ron Dufresne, Jim Clayborne, SGT - Installer Scot Stewart - Scot Stewart Casaba Ranganath - Lead Design Verification Ron Tyrie - Operations ALARA-Ken Young

" Craig Miller - CR3 Containment Root Cause Team Scott Mawhinney, P.E.

AREVA NP Inc.

Engineering Supervisor BOP Structural and Engineering Mechanics Scott.mawhinney@areva.com Thomas J. Rowe, S.E.

Wiss, Janney, Elstner Associates, Inc.

Principal Engineer trowe@wie.com B.8 Quality Class Determination Quality class of individual components and materials required for this EC are as follows:

1. The containment building is a Class I Structure (Safety Related) as described in the FSAR Sections 5.1.1.1 and 5.2.1 and the Design Basis Document for the Containment, (Ref. 2.1, Tab 1/1). The primary function of the reactor containment building and its steel liner is to house the primary nuclear system and to provide biological shielding BOO Design Page 23 of 24

PCHG-DESG Engineering Change 0000075219RO from the fission products that could become airborne under accident conditions. Its failure could result in the uncontrollable release of radioactivity and its integrity is vital for the safe shutdown and isolation of the reactor.

2. Tendons, tendon anchorage including stressing washers, shims and tendon grease are all Safety Related. These items ensure the structural integrity of the containment building.

Therefore, the overall quality classification of this EC shall be Safety Related.

BOO Design Page 24 of 24

PCHG-DESG Engineering Change 0000075219RO CA1 Document/Drawing and Equipment Database Mark-Ups Controlled documents requiring revision are listed on the EC Affected Document List (ADL).

Drawings required for turnover are designated with the "OpSVc" flag on the ADL. Document changes may be indicated by document mark-ups or by "Description Of Change" provided in the tables below.

C.2 Updates of Controlled Documents/Drawings There are no design records that require updating as a result of this modification. Any evaluation or removal sketch shall be within the body of this EC.

C.3 Other Required Updates 0S1R~' foS 4_

COO Mark-up Page 1 of 2

PCHG-DESG Engineering Change 0000075219RO C.4 Equipment Parameter Notes CAUTION Parameter Notes are placed under Revision Tracking & Control beginning with the V1 0.0.4 upgrade of PassPort (installed on December 10, 2006). Prior to V10.0.4, special rules were required for processing EDB Parameter Notes. Prior to V1 0.0.4, since parameter notes are not part of the EC PassPort report which becomes a QA record, a parameter note with a pending change should be captured in the table below to preserve the QA record. Changes to parameter notes created after V10.0.4 should be processed in the same manner as any other EDB change under Revision Tracking & Control, and are not required to be captured in the table below.

(Select Table/Select/Table, copy Ctrl-C, and paste Ctrl-V the following table as many times as necessary.)

U Syte Tag # or Eqimn Parameter NONE I

I C.5 Equipment Document References Equipment document references in the Equipment database are not under PassPort revision tracking and control. They should be listed below (Title is optional):

I ~

~

Uni Syte Ta orEupmn 4

.4.

4 4

-4.

4 I

4 I

I I

4

+/-

4 4

+

COO Mark-up Page 2 of 2

PCHG-DESG Engineering Change 0000075219RO D.1 Installation Package The following information is used to specify installation requirements to be used for planning the work package. Installation sketches are provided in the sketch section of the EC.

D.2 Installation Requirements Prerequisites and Precautions

1. Pre-job brief shall be conducted prior to commencing project in the field. Topics should include OE 14720, OE 29756, and Hydrodemolition Lessons Learned documented in NCRs 358636 and 358653.

2. Contact WCC prior to beginning work in the field.

3. Control of transient combustibles is to be maintained in accordance with AI-2200.

4. Housekeeping of the work areas shall be maintained in accordance with Al-1000 or approved SGT equivalent.

5. Erect any required scaffold in accordance with MNT-NGGC-0004 or approved SGT equivalent.

6. Any hazardous waste that is produced by activities implemented per this EC shall be handled and shipped in accordance with Procedures EVC-SUBS-00016, EVC-SUBS-00008 and AI-1820.

7. Any non-hazardous waste that is produced by activities implemented per this EC shall be handled and shipped in accordance with Procedure AM-1820.

8. Strain gauges have been installed by WO 1636782-04 and are functional.

9. Perform Hot Work in accordance with FIR-NGGC-0003.

10. Verify all detensioning work associated with EC 75218 has been completed prior to concrete removal.

11. Installer to verify dosimetry requirements with Radiation Protection prior to commencing work in the field.

12. Sensing Systems has verified that the original plant strain gauges, which are attached to the embedded reinforcement, are not functioning. They shall be removed as they are uncovered during the demolition process. Strain gauges 'installed for monitoring during detensioning shall be removed under the direction of Sensing Systems as the wall being prepared for removal.

13. Lesson Learned concerning hydrodemolition runoff as documented in NCRs 358636 and 358653 shall be reviewed prior to start of work. Only qualified or designated personnel are allowed to remove storm drain covers to adjust the flow of pooling water runoff.

14. All hydrodemolition equipments shall be tested prior to start of work.

15. A safety net or other similar device shall be erected around the hydrodemolition equipment to prevent debris from falling and injuring personnel

16. Discharge of hydrodemolition into settling ponds may not commence until both site chemistry and RP have cleared samples as being acceptable to do so.

Hydrodemolition may continue provided wastewater and rubble are collected in temporary bins/tanks until they can be cleared. Activities shall be in accordance with EVC-CRNF-0002.

17. Use of chemicals for this activity are subject to the requirements of CHE-NGGC-0045, NGG Chemical Control Program.

18. Dikes shall be installed around equipment, especially chemical storage, in accordance with WP-106, "Storm Water Discharge from Diked Petroleum, Chemical, DO0 Install Page 1 of 7

PCHG-DESG Engineering Change 0000075219RO and Equipment Storage Areas." Barriers shall be specifically installed around tendon gallery sumps SDP-3A and SDP-3B to prevent potential hydrodemolition runoff from the tendon sheaths from entering into the pumps.

The pumps shall be tagged out at the discretion of site operations. Temporary sump pumps shall be installed to remove any runoff in the tendon gallery and carry to a portable collection facility. Water shall be examined by site chemistry and RP prior to disposal and/or discharge. Additional precaution shall be noted for the potentially open equipment hatch. Should the equipment hatch still be open, barriers shall be installed by SGT so as to prevent water and/or concrete slurry from entering into the CR3 RB during hydrodemolition activities.

19. The CR3 RB containment coordinator or project lead should be notified prior to the start of hydrodemolition activities. This person shall inform all personnel within containment in the immediate area that hydrodemolition activities will commence and noise levels may drastically increase.

Removal of Concrete

1. Overview of concrete removal is shown on SK-75219-COO1. Additional concrete may be removed as required to assure complete delamination removal. The sketch is to serve as a starting point for removal. The intent is for hydrodemolition to remove the general area while knocking loose any of the delaminated concrete. The hydrodemolition process should cease as the centerline of the hoop tendons is reached. Greater depths may be removed under the direction of the responsible PGN civil engineer under the guidance of the ACI concrete repair manual. In certain circumstances, hydrodemolition shall be discontinued and certain hand removal methods shall be used such as pneumatic or hydraulic impact breakers, needle guns, lance hydrolazing, or equivalent. The use of those tools and depths exceeding 10" shall be reviewed and approved by the PGN responsible civil engineer prior to their usage for localized removal.

2. Hydrodemolition shall be the primary method of concrete removal. No single pass of hydrodemolition shall remove more than 4" of delaminated concrete. Pressure shall be reduced as the depth of delamination is approached to minimize jets spraying the hoop tendon sheaths as well as sound concrete behind the delamination.

Hydrodemolition may be used at the reduced pressure to clean the surface and obtain the desired surface profile on the sound concrete but should not be used to significantly remove the concrete past the centerline of the horizontal hoop tendons.

3. The maximum depth of removal shall be a typical 10". This is the centerline of the hoop tendons. Spalling of localized areas behind the hoop tendons is expected.

Delamination extending beyond hoop tendons shall have a minimum of 2" excavation around., the tendon to ensure a good bond when the concrete is replaced. All obviously loose pieces of concrete shall be removed. When spalled areas pass beyond the 10" depth, refer to note 1 as hand methods may be required to complete the removal of unsound concrete. As before, all loose concrete shall be removed from the containment wall. Areas that require localized attention to provide further removal shall utilize a less invasive method which may include but is not limited to mechanical or hydraulic impact breakers, needle guns, or lance hydrolazing. The usage of alternate removal tools shall be approved by PGN civil engineering prior to their usage on the wall past 10".

DO0 Install Page 2 of 7

PCHG-DESG Engineering Change 0000075219RO

4. Rebar should be cut using saw-cut method only for those rebar that will utilize a lap or mechanical splice. Flame cutting is permissible to advance removal work in the field provided that cut is made no closer than 6" to the prepared end. The heat affected zone shall be removed before any final splicing/coupling takes place. Rebar shall be discarded and is not to be reused for work associated with EC 75220. Any original plant construction aids may be. removed as needed by SGT by any safe, reasonable method. Tailings for the embedded #8 rebar of a minimum 9" for an approved mechanical coupler shall remain for tie-in of new rebar as shown on SK-75219-COO1. Splices shall be planned around horizontal tendon ducts and adjacent rebar as required by EC 75220. Final lengths may be more than 9" so as to develop alternate code splice requirements and staggering requirements (Within 36 to 80 bar diameters may be cut to utilize a lap splice). Rebar coming up from the equipment hatch (#11 bars) as shown on Drawings 421-032/ 421-040 and rebar projecting downward from the ring girder (#18 x 24'-0" long) as shown on Drawing 421-036 SHALL NOT be cut unless prior authorization is obtained. Additional #9 hooked bars as shown on 421-036 extending from the buttresses shall also be preserved. If rebar other than the identified #8 requires cutting, stop work and notify Progress Energy design engineering to provide design review and requirements at that time. Should interferences prevent the use of saw cutting in some areas, SGT should contact PGN civil engineering for acceptable alternative on a case by case basis. The resolution shall not impact the ability to install necessary mechanical couplers as described in EC 75220, if needed.

Preparation of Concrete Surface

1. Concrete surface shall have a minimum surface profile of CSP-6 or greater as described by ICRI 03732 in Attachment ZOO. Based on ICRI 03732 and ICRI 03737, hydrodemolition methods achieve this minimum surface profile. Other methods may be used at the discretion of the PGN civil design engineering in accordance with the Concrete Repair

Manual, Third

Edition, to remove localized areas of unsound/delaminated concrete. Methods which have a high tendency to produce micro-cracking will not be allowed.

2. Prepare all edges as described in ICRI 03730 (page 7 of Attachment Z01) as applicable. Saw cut a minimum 11/22 along cut line as shown on SK-75219-COO1, however, cut shall be made as deep as reasonably achievable without cutting remaining rebar tailings. The use of mechanical impact breakers shall not be allowed to prepare the edges to minimize micro-cracking in these locations. Remove all feathered edges.

3. After all cutting/hydrodemolition the surface shall be cleaned of all dirt, oil, grease, laitance, slurry, and loosely bonded aggregates. As noted in ICRI 03730 and ICRI 03737, if hydrodemolition is used, cement and particulate slurry shall be removed before drying and hardening.

4. Concrete sounding shall be performed in all removed area locations using ASTM D 4580 as a guide (Reference Procedure B, Attachment Z02). All unsound concrete shall be removed. A typical grid spacing of 12"x12" (+3"/-6") should be utilized for sounding. A 16 oz ball peen hammer or long threaded rod is recommended for the DO0 Install Page 3 of 7

PCHG-DESG Engineering Change 0000075219RO sounding process. The sounding object should be struck against the concrete surface at the predetermined spacing. The personnel performing the sounding should listen to and note the resulting "ringing" sound. A tone change more like a dull "thump" or "thud" would be indicative of a delaminated section of concrete. Those delaminated regions should be removed with less intrusive hand methods such as a needle gun or equivalent.

5. Any noticeable cracking at the surface should be mapped. PGN design engineering shall examine this mapping and as well as the concrete surface in order to communicate acceptance criteria for leaving, removing, or repairing. If the crack is unable to be removed or is determined to be left as-is, EC 75220 shall provide the repair and/or acceptance criteria for leaving the crack untouched.

This includes those areas particularly around the area of the liner stiffeners as identified in NCR 370873. Any specific area of interest should be documented and captured as part of the mapping process to ensure it is correctly addressed. It should be noted that cracking is expected to form above and below the construction opening as a result of detensioning activities (reference EC 75218). Particular attention should be given to those areas during surface preparation in order to identify those cracks.

6. A cursory review of any remaining reinforcement shall be performed by the PGN responsible civil engineer to note any significant degradation/damage to the rebar prior to the implementation of EC 75220 to prevent any significant delay in the work schedule.

Surface Testinq Considerations:

Testing for adequate surface preparation shall be implemented by SGT field engineering under the direction of the PGN civil design engineering using ACI 503R, Appendix A as a guide (See Attachment Z03, Pages 27 and 28).

1. Cut 1" Aluminum T-bar into segments so as to create 1 in2 bonding surface area on the flange.

2.

Drill a hole in the web portion of the T-bar for subsequent tension pull attachment

3. Abrade flange of T-bar with Crocus Cloth or equivalent

4. Using a fast setting epoxy, affix the T-Bar to the surface of the prepared concrete. Epoxy strength should meet or exceed the strength of the concrete, or 5000 psi compressive strength and 200 psi tensile strength

5. Score around the edge of the flange to ensure only 1 in2 of bonding surface area.

6. Allow epoxy to set per manufacturer's recommendations

7. Fabricate testing rig as shown in figure A.5 of Attachment Z03. Dillion Dynamometer may be substituted with equivalent tension type dynamometer with capacity of 500 lbs minimum. Resolution shall be such that values can be recorded in 10 lb increments.

Hardware may be substituted as required to allow fit up to bonded aluminum T-bars.

DO0 Install Page 4 of 7

PCHG-DESG Engineering Change 0000075219RO

a. Load bonded T-Bars at a uniform rate. Record the force value at which the T-bar debonds and note the type of failure on the Attachment Z04 data sheet.

b. Concrete bond strength should meet or exceed 200 psi.

c. Repeat steps 1 through 7 at a rate of 1 test for every 100 sq. feet of prepared concrete surface or as best as reasonably achievable. Tests shall be re-conducted for areas where inadequate bonding strength is determined.

Additional surface preparation may be required to obtain surface with adequate bonding strength.

d. Testing may be terminated at the discretion of PGN civil engineer if results show consistent adequate bond strength or testing is shown to not be practical.

Subsurface Micro-Cracking Test Considerations:

Testing for adequate subsurface strength shall be implemented by SGT field engineering under the direction of PGN civil design engeering using ICRI 03739 as a guide (See Attachment Z07).

1. Drill 2"corebores a minimum of 6" deep at 3 random locations throughout the prepared surface area.

2. Affix a metal disc as described in Attachment Z07 with the same epoxy used to affix the aluminum T-Bar above and allow to set per manufacturer's recommendation.

3. Using skill of the craft attach the rigid disc to the pullout rig created for the above testing.

4. Apply a load at a uniform rate and record the load at which the core breaks. Stress levels should meet or exceed 200 psi. Additional surface preparation/excavation may be required if testing shows inadequate strength.

5. Repeat the test as described in ICRI 03739 a minimum of three locations at the discretion of the PGN civil engineer. Testing may be terminated if conditions prove impractical.

Monitoring for Excessive Thermal Gradients across the Unreinforced Containment Wall Based on review of the MPR analysis S10-0004, a 100 F shall be accounted for and maintained during and after the concrete removal process.

1. Thermocouples per Attachment Z06 (or equivalent) shall be attached to the RB containment liner and exterior concrete wall at the discretion of CR3 operations and the CR3 Containment Design Basis Analysis team.

2. A rolling 7 day rolling average shall be observed by operations. The delta temperature difference between internal containment temperature to exterior temperature shall be maintained at less than 100 F by using OP-417. The limit on the ambient temperature inside containment is 600 F.

3.

If the thermal gradient approaches 80 F, an evaluation will be made by engineering to determine if forecasted temperatures could result in a sustained gradient greater DOO Install Page 5 of 7

PCHG-DESG Engineering Change 0000075219RO than 100 F. If such a gradient is judged possible then appropriate actions shall be taken and the affected organizations shall be notified at this time.

4. Internal containment temperature shall be maintained by site operations utilizing OP-417. Scaffold and sheeting shall be erected as needed to maintain temperature on the exterior surface. SGT shall be responsible for supplying heaters to maintain the temperature on the external surface within the "tented" area.

D.3 Label Requests Labels requiring change as a result of this EC include: NONE DOO Install Page 6 of 7

PCHG-DESG Engineering Change 0000075219RO D.4 EC Parts List Parts or other materials required by this EC are tabulated below. Any unique or long lead procurement actions are indicated in the description.

Feet 2

TBD/

Epoxy, Fast-set, MFR, STD., Min bond strength = 200 psi and QL-4 QL-4 Each minimum compressive strength = 5,000 psi TBD = To be determined 4

4 4

4-

.4-L 1

t t1"_

d DO0 Install Page 7 of 7

PCHG-DESG Engineering Change 0000075219RO E.1 Testing Requirements Unique Prerequisites, Precautions, Limitations, Initial Conditions, and Outage Requirements:

In-situ surface preparation testing will be required prior to concrete placement per EC 75220. Surveillance may be required for to monitor surface final bonding surface conditions prior to concrete placement. Refer to Attachments ZOO and Z01 for industry guidance on surface preparation. Other required ASME Section XI, Subsections IWE/IWL as well.as ASME Section III inspections and testing shall be implemented under interfacing ECs 75218, 75220, and 75221.

Test and Acceptance Criteria:

Reuire Tes Prcdr D i~ es U

ign i

E ~

Inpt P

aram (J

eter/

141C Fuc io Acetac Cr((.II.fUiteia for i

V O

Or Method Bonding surface preparation ACI 503R-93 (Reapproved 2008)

Reference Installation Instructions and Attachment Z03, Pg 27-28.

Bond strength meets or exceeds 200 psi. 200 psi is the minimum design tensile strength of the concrete as described by DBD for the Containment. At that stress level the concrete anywhere-in the structure is just as likely to crack as the bond interface between existing and new concrete.

N Subsurface in-situ strength test ICRI 03739 Core strength meets or exceeds 200 psi. 200 psi is the N

minimum design tensile strength of the concrete as described by DBD for the Containment. At that stress level the concrete anywhere in the structure is just as likely to crack as the bond interface between existing and new concrete.

EOO Testing Page 1 of 1

PCHG-DESG Engineering Change 0000075219RO F.1 Turnover/Closeout Summary Based on a review of Section 9.3.4 of EGR-NGGC-0005 and the scope of this Engineering Change, turnover to operations SHALL NOT be required based on the following:

No Priority 0 documents are affected No POM procedures are affected No impact to electronic equipment data No Tech Spec Change is required No impact to surveillance test schedules No impact to Clearance software No impact to Technical Specification tracking software No training requirements No testing requiring Engineering review of results identified No labeling requirements Closeout Summary All Work Order Tasks are status FINISHED or COMPLETED Assure AR's are COMPLETED or CLOSED Prior to EC Closure, a "Post-Job Brief" will be held after EC 75000 has been installed to discuss and evaluate the various aspects of the EC. This briefing will be chaired by the Responsible Engineer or his designee and will be attended by representatives of the organizations with insights into how well the job was accomplished. The attendees will be determined by the RE based on input needed and availability of appropriate individuals. Reference AR 365187365187

Catalog and Bill of Materials Impact BOManufacturer:

Model:

Version:

NONE Prpsed-t I.

+

FO0 Turnover Page 1 of 1

PCHG-DESG Engineering Change 0000075219RO GA1 Installation Sketches S

A -ueiaminaieu

., oncreie riemovai ueiaiis SK-SK-SK-SK-SK-SK-GOD Sketch Page 1 of 1

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CONSTRUCTION OPENING SECTION B-8 CONSTRUCTION OPENING SECTION C-C B

PLAN VIEW ELEVATION VIEW SECTOE-A-KFF1P1tE L

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NOTES:

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PCHG-DESG Engineering Change 0000075219RO H.1 Risk Management

,Scop ofWok EC 75219 is the third phase in a multi-phased approach in the repair of the CR3 RB containment building identified per NCR 358724 as follows:

1) Crack Arrest (EC 75000) - A series of cuts will be provided into the delaminated concrete.

These cuts will provide a path of stress relief during the detensioning process. Two horizontal cuts will be made, one above and one below, the steam generator replacement opening. The length of the cuts will not exceed the area of construction opening. In addition to horizontal cuts, vertical cuts will also be installed above and below the contstruction opening at Azimuth 1500.

The cuts will run between the currently detensioned vertical tendons at a depth only to cut embedded rebar. This is to minimize cutting active hoop tendons which exist above and below the current containment opening.

2) Detensioning (EC 75218)- A Finite Element model developed by MPR Associates, Inc. shall be completed to show the necessary detensioning and re-tensioning sequence as well as compliance with the appropriate bases. The detensioning implemented by this phase will ensure adequate prestress can be returned to the Reactor Building structure.

3) Concrete Removal (EC 75219) - This EC will address the removal of the existing delaminated concrete. This is to facilitate the placement of new concrete per EC 75220. The removal of the delamination will require the detensioning of vertical and horizontal tendons within the affected region as prescribed in EC 75218. All steel reinforcement (rebar) exposed within the opening must be cut and discarded. Once the delaminated region is removed, phase 4 EC 75220 may be implemented. Removal will be accomplished via a combination of hydrolazer and/or mechanical methods (chipping).

4) Concrete Placement (EC 75220) - This EC will address the replacement of the delaminated concrete with new concrete. Mix and installation shall consider criteria evaluated per EC 63016 to originally restore the containment opening. Critical concrete characteristics such as creep, aggregate type, testing requirements, etc. shall also be considered as a part of this phase.

5)

Re-tensioning (EC 75221) - This EC will address the final re-tensioning sequence to restore prestress back into the concrete containment shell once the replaced concrete has adequately cured. Final MPR FE analysis results shall be incorporated to ensure the applicable design and licensing bases requirements have been met.

Risk Cr-ia 0v 0utons 0*

0 As noted above, this EC will address removal of the concrete only. Based on the available methods of removal, hydrolazing and mechanical chipping, risk of damage to the underlying reinforcement and tendon sheaths exists. While the conventional reinforcement will be removed as a result of this EC and ultimately replaced, damage to the tendons is possible and must be minimized, particularly to the flexible conduits in the region around the equipment hatch. Additionally, due to the scale of the removal, consideration must be given to all the personnel safety risks associate with removing such a large volume of concrete. It should be noted that this Risk Worksheet is preliminary awaiting final resolution of the Root Cause, particularly. Work shall be performed during plant No Mode to prevent adversely affecting the integrity of the structure while the removal takes place.

Probability: C1 E..

rH.Em EIL HOO Reviews Page 1 of 25

PCHG-DESG Engineering Change 0000075219RO Consequence: E1 C2 [- 3 I

'Basis for P 0 0

• 0 -u"I,, :

The activity mitigation/avoidance strategies as well as the basis for probability have been documented below, Each item as individually screened as medium risk or low risk, therefore, the overall risk of this EC shall be medium in accordance with EGR-NGGC-001 1.

Rik ls-s S.

,Risk~*

Ris RikRsos 0cin Parameter iýRsonse Infrequently performed task related to concrete removal of RB containment wall.

r-Avoidance r iAcceptance,,

',P Mitigationbmi!,

Design and Construction Engineering Oversight - Using hydrodemolition and other large scale equipment to create an opening in the RB wall is an activity that is infrequently performed at CR3. However, using hydrodemolition equipment to create such an opening has been successfully employed at numerous other nuclear plants in support of their SGRs and reactor vessel closure head replacement projects. A majority of the CR3 Delamination repair team, both engineering and construction personnel have extensive prior experience working on SGRs and (RVHRs) and are cognizant of the potential problems associated with hydrodemolition and mechanical demolition. Final Root cause determination will be considered before proceeding with any one removal option.

Previous Experience - The vendor performing the hydrodemolition (Mac and Mac, EXPECTED), has been in the business of hydrodemolition for over 30 years and will be responsible for operating the equipment.

Installation Instruction Precautions: The installation instructions will contain a precaution for the hydrodemolition contractor to reduce water pressure as needed before exposing the underlying tendons.

This is to reduce the risk of penetrating the sheath. The consequences of further damage during the removal process are considered high, however, this phase of work is merely to allow the final repairs to occur. Proper engineering oversight during the removal process will ehsure removal is done in a safe, efficient manner. Additionally, damage that could occur during the removal will be evaluated and repairs made during the subsequent interfacing EC 75220. As such the likelihood of irreversibly damaging the structure is considered extremely low. Therefore this risk parameter is considered medium.

+/-

+/-

Personnel safety due to large volume of concrete removed and associated working at heights.

r Avoidance rP Acceptance F* Mitigation Concrete removal and handling of associated equipment will involve the dangers of working at heights. Personnel access tothe various scaffolds and work platforms must be limited to those individuals that have a need to actually be on the platforms. The pre-job brief should also emphasize the potential danger from dropped objects, especially considering the heights involved when working on the containment building roof or suspended on the work platforms.

Adherence to Vendor Procedures and Training is critical.

Incorporation of relevant OE shall also be incorporated into necessary pre-job briefs.

Adherence to CR3 Procedures - All work performed relating to this EC will be in accordance with SAF-NGGC-2172, "Industrial Safety" or HOO Reviews Page 2 of 25

PCHG-DESG Engineering Change 0000075219RO SGT equivalent. All appropriate safety equipment is to be employed during the performance of this modification (e.g. eye, face, hearing,

,i.hand, foot protection, fall prevention / protection, respirators).

Personnel working on scaffolding must be familiar with the requirements for working at heights. All work controlled areas will be marked and tagged per AI-1816, "Industrial Safety Signs and Tags" or by equivalent SGT process.

While the consequences of the injury are high related to the removal work, the probability is considered extremely low provided all Site procedures are appropriately adhered to. As such this risk parameter r is considered medium.

Accelerated The various phases of the delamination repair project are ongoing in schedule could parallel to the root cause investigations. There are significant allow for consequences if the repair techniques would make the crack larger approval prior or not even solve whatever crack initiating event caused the to final root delamination. Surface preparation requirements dictate only a few cause methods will create the surface required for new concrete placement.

determination 17 Avoidance Best industry practices shall determine the recommended technique for both removal and surface preparation. The least invasive method rF Acceptance' which would damage the structure shall be considered. To ensure significant damage has not been sustained in the structure, in-situ pullout testing of the subsurface will show the necessary strength remains in the concrete subsurface. This testing will be in accordance with ICRI 03739. While the consequences of procedding without final root cause may be high, probability is considered extremely low as any additional areas of damage sustained during removal may be repaired before final concrete placement. Therefore this risk parameter is considered medium.

Multiple parties The containment team consists of both design and implementation involved such FJ_ Avoidan ce individuals. These individuals are required to interact during pre-job that errors may and kick off meetings. Final EC review by members of both parties be introduced

- Acceptance would prevent approval of product. Therefore, the consequences of via an overlooked design item may be high, however the constant review communication P. Mio process would make it an unlikely occurrence. Therefore this risk channels parameter is considered medium.

HOO Reviews Page 3 of 25

PCHG-DESG Engineering Change 0000075219RO H.2 Validation Plan The Responsible Supervisor should complete the following validation plan with the Responsible Engineer at the initiation of the EC (see EGR-NGGC-001 1).

PrdctE Prcss/oo 6us e

Inera Al ote Eg To Be Stag EC*

EC!

PoutSIpeetd I At Initiation Validation Plan H

H U

NO Risk Determination R

R 0

r7 Risk Response Planning R()

R 0

F Project kick-off meeting X

0 0

r7 Pre-job briefing R

R NA rV Formation of an EC Team X(b X*b)

NA F

Scheduling/Work Management X

X 0

Development In-process review - 0% Design X

0 Waived Phase Challenge In-process review - 30% Design XXm 0

Challenge r_

In-process review - 70% Design XXb) 0 Waived Challenge In-process review - Final Design XX~b 0

Waived Challenge Source review 0

NA NA r

Owner review X

NA NA r

Error Prevention Tools (STAR, 0

0 0

SAFE, OAQ-3, etc) ro Design Review Board -

X X

0 Waived Conceptual Design Review Board - Final X

X 0

r*

Engineering change checklist R

R 0

Outsource management R

0 0

r checklist Procurement vendor oversight 0

0 0

r checklist Supervisor EC Approval R

R NA Checklist r_

EC Implementation Checklist 0

0 NA r

Post Post-job briefingý")

X X

0 r_1 I

Implementation

+

4 This EC is considered medium risk as discussed in the Risk Management Section. A significant amount of work completed under EC 63016 will be reviewed an incorporated as applicable. This EC is one of several smaller EC's as a result of the containment delaminated repair plan. This EC is formed in part by taking information from EC 63016 and reusing it where possible as well as building upon EC 75000 for crack arrest. The EC scope will be reviewed by plant personnel in a Final DRB. Management has requested additional oversight by scheduling a 30% challenge with design team participants to ensure all technical requirements for the delamination removal are addressed.

The final DRB is sufficient to address technical and plant concerns so the 100% Design Challenge will also be waived. Concurrence of the risk assessment and this validation plan will be performed by CR3 Design Superintendent, Keith Allen. Post Job Brief will be performed under NTM AR 377697377697

Notes:

HOO Reviews Page 4 of 25

PCHG-DESG Engineering Change 0000075219RO

1.

Required use of processes/tools per this procedure apply to PCHG-DESG, PCHG-ALTR and TCHG-DESG ECs (except child ECs) only. These tools are optional for all other EC types

2.

Outsourced ECs are ECs which are developed by vendors. Internal ECs are ECs developed in-house.

3.

0 - Optional, X - Required (unless waived and waiver basis documented), R - Required.

4.

Design Superintendent approval is required for ECs screened as high risk or for waiving DRB not previously waived for this application.

5.

For ECs determined to be high risk level.

6.

Initiate an NTM for scheduling purposes when the validation plan is approved.

7.

For ECs determined to be medium or high risk level.

H.3 Reviewer Comments Select, copy, and paste the table below into a WORD file and e-mail message to reviewers.

Select (Table/Select/Table), copy (Ctrl-C) and paste (Ctrl-V) tables from reviewer's responses below. Have reviewer sign EC milestone when comments are resolved.

Discpie/rga Re ie Scp ofRve I

Im A IPla*A ml I

f f

U 1/VL.U b

lj_=,VU'~E

'/o u5esign Rleview-.

- j I R. Portmann I IWE/IWL I 12/28/09 1 No I

I~ Ite Comen Resolutionl~ak!

I 1

• econ.*.]).*,

ecu n r-1. 1. I). -

Consider generalizing these paragraphs to eliminate future revision of this EC due to potential chanaes in EC 75000.

-Ane secons nave aeen s.mplTleD.

2 Section B.2, 2 nd para. - Delete "within the Removed.

boundaries of the delaminated region" 3

? Cutting of rebar to be included in this Rebar will be cut and removed as EC?

described in scope. Rebar tails will remain as required for replacement.

4

? Inspection of the cut rebars to be Inspection of the rebar is not to be part of included in EC75220?

this EC scope 5

? Hydrodemolition and/or concrete Equipment set-up shall be included in chipping equipment set-up and tie in to either this EC or another EC based on site structures to be included in this EC?

availability of info and status of potential EC.

6 Section E.1 Testing Requirements-Add Added.

a statement that the ASME Section Xl, Sub-section IWA and IWL and the ASME Section III inspection and testing requirements are to be addressed under EC's 75218, 75220 and 75221.

RP 30%

Ken Youn ALARA 01/06/10 1

RCA entries at hole will require EDs /

Prerequisite added to installation section TLDs but no frisking should be required.

to require craft to verify dosimetry RCA should be posted for dose rates requirements prior to commencing work HOO Reviews Page 5 of 25

PCHG-DESG Engineering Change 0000075219RO only. This would require a sign-in and in the field.

sign-out process only.

2 3

4 5

o perations I 30% desi n review R on T nre Operations SRO 101/06/10 1 No 1

A - Incorporate CR3 LL from recent LL incorporated into A.6.

experience 2

B - In the RB design discussion, consider Incorporated listing the imposed lower temperature limit of 600 F for interior areas during shutdown conditions.

3 B - Page 5 item 5 - in the discussion of Added additional wording and bases thermal gradient, we must not just consider but monitor and control within design limitsas determined by the analysis for unreinforced concrete.

4 B - page 7 item 16 - consider adding the Added additional wording and temporary local temperature monitoring corresponding evaluation in B.6.16 instrumentation to be added (2 inside, 2 outside) with remote monitoring capability.

5 B - page 8 item 26 - Consider Added additional wording and mentioning the dropped load evaluations corresponding evaluation in B.6.26 to ensure RW flume capability (SF Pool cooling) is not lost during this EC execution 6

D - Nothing here?

Added during completion of final product.

7 J - engineering checklist has not been Engineering Checklist to be completed completed prior to issuance for final review.

D e

Rve S

of Review ReiwrDscpieDt

'froe S

Siecl Rick Curry x4215 IMechanical T1 /6/10 Section D.5, EC Parts List, recommend Added parts based on surface testing adding "none" or "none required".

HO0 Reviews Page 6 of 25

PCHG-DESG Engineering Change 0000075219RO 2

Need to add Procurement Engineering as So added.

a milestone signoff.

1 EC 63020 should be included as Added.

reference for applicability of using the mobile crane for lifts and the associated loading calculations 2

References 9.2 -the current numbers are Incorporated.

235 for the License Amendment and 81 for the Bases revision. The bases revision will change on Jan 15, 2010 3

Design Inputs 1. -in describing the Incorporated containment the language that is used in the FSAR is 'uncontrolled release' vs.

'uncontrollable' 4

Design Inputs 19 -you include Removed statement describing LODHR references to modes 5 and 6 and LODHRt Throughout this EC we will remain in no Mode and there can be no LODHR event involving the containment.

5 incntaie Int thef angugentiht iu alse ine it uncontrollable'tio EC in desisn input 17 2

Is monitoring required during removal?

Based on discussion, monitoring does not add an significant value to the de-stressed (detensioned) structure in the region of removal.

3 4

5 Dicpie/rga Reie

-Sop ofeve Installer/SGT "30%

Design Challene

_1 T_

I noe Requred I Bill Alumbau.lh 1/6/10 Section B.2, c

Te Para, 2ng Cent. Rebarl pe states rebar will be discarded.

2 sbe removed and disposed, not reused.mBdo r

o HOO Reviews Page 7 of 25

PCHG-DESG Engineering Change 0000075219RO Recommend revise to agree with Section H.1.3 which states that the rebar will be discarded.

2 Section B.4.1, Last Para in section.

Reworded.

Recommend rewording of sentence beginning "The function of the containment... " to "The design function of the containment building will not be adversely affected and all code requirements and design margins will be maintained during the delamination removal and repair."

3 Section B.4.5, 1st Para, 5th Line. Loads Hydrodemolition loads are considered as associated with hydrodemolition are a result of evaluation in EC 63016/EC considered. Hydrodemolition is to be 75000 and are minor with respect to the used in the removal of the delaminated overall strength to the structure.

area. Do current analyses envelope the use of the same process in the MPR analyses?

4 Section B.4.5, 1st Para, 5 th Line. Thermal The monitoring parameters have been gradients generate the higher stresses in discussed in B.6.16.

no mode with detensioning. Identify the design parameters and controlling construction provisions.

5 Section B.4.6, Water Requirements, 3 rd B.4.6 has been reworded to clarify Line. Clarify that SGT will provide access responibilites.

and water sample will be obtained and test performed by CR3.

6 Section B.4.6, Waste Water, 1st Para. 1st B.4.6 has been reworded to clarify Line. Same comment as No. 5 responibilites.

7 Section B.4.6, Waste Water, 2 nd Para.,

B.4.6 has been reworded to clarify 1st Line, Progress Energy provides water responibilites.

tanks for storage. SGT provides piping for delivery from wells to tank and from tank to work site.

8 Section B.4.10, 1st Para, 2 nd Line. "No Removed.

additional damage." Crack arrest, chosen demolition method was selected because it was determined not to be a contributing cause, and inspections will be performed before and after demolition to assure that the delamination has be been removed.

But there is the potential that additional delamination may be encountered which would make this phrase incorrect.

Recommend deleting sentence, previous sentence states that the crack is removed should be sufficient.

9 Section B.4.10, 1s' Para, 3nd Line.

Reworded.

"Cutting of tendon sheaths..." Flex I

HOO Reviews Page 8 of 25

PCHG-DESG Engineering Change 0000075219RO tendon sleeves will most probably be damaged by hydrodemolition and with demolition there is always the possibility a sleeve will be damaged. Recommend rewording and mention that tendons will be removed from known sleeves containing flexible sections to minimize damage potential to the tendon.

Remaining tendon sleeves are to be inspected and repaired prior to containment restoration.

10 Section B14. 1 st Sentence. Boundaries Drawing SK-72519-CO01 shows the of the section to be removed is to be removal area.

identified to width, length and depth or as described on a drawing.

11 Section B14. 2 nd Sentence. Rebar will Added wording.

be excavated by hydrodemolition then cut to length to leave a tail. If configuration requires a shorter length or in the even the cut is adjacent to a splice where the bar is removed by demolition then drill and grout may be required. 2 nd sentence needs to be generalized stating that a code splice will be developed between the new rebar and the bars in the undisturbed concrete.

12 Section B4.19, 6t* line. Recommend So deleted.

deleting the phrase 'While defueled," The Containment structure creates the Il/I condition. If the containment meets code loading conditions, including seismic, with the tendons detensioned then it remains seismic cat 1 in the degraded state. IF it does not then RG 1.29 and 1.206 is going to drive a Il/I evaluation because of the adjacent Cat. 1 structures. Defueled state just means there are no Cat 1 components inside containment. Based upon previous statements the containment with detensioning is code qualified to dead + Live + seismic +

wind/tornado/hurricane as applicable.

Pressure is eliminated (no fuel) which is the controlling load for the containment.

HOD Reviews Page 9 of 25

PCHG-DESG Engineering Change 0000075219RO I Procurement Enine Final Comments Rick Cur x4215 Mechanical 1/27/10 1

Section D.5, EC Parts List, see table Incorporated below for comments.

Installation Design No. Unt ume ee I

adVrso)o 1

TBD/

T-BAR, 1" Aluminum, MFR. STD., Length as QL-4 QL-4 Feet

_Required 2

TBD/

Epoxy, Fast-set, MFR, STD., Min bond strength QL-4 QL-4 Each

200 psi and minimum compressive strength

5,000 psi.

TBD = To be determined.

.j. ________

I _________

Dicil 0ePoa Reie Scop of Revie Environmental Ron Johnson/Lloyd Environmental Permits 1/27/10 Tardif 1

Section A.6; Operating Experience. We Lessons Learned added to A.6 and might want to add references CR3 NCRs references added to Section B. Additional 358636 and 358653, related to a release prerequisite added to installation section.

of industrial waste water to the canal associated with the SGR hydro-demolition activity.

2 Section B.3.6, NGG Procedures, add:

Added CHE-NGGC-0045, "NGG Chemical Control Program".

3 Section B.3.7, Plant Procedures, add Added reference to SP-736K, "Reactor Building Hydro Demolition Release to the Settling Ponds"; this procedure was developed for SGR and should be used again.

HOO Reviews Page 10 of 25

PCHG-DESG Engineering Change 0000075219RO 4

Section B.3.10, Other

References:

add Added documents: EVC-CRNF-0002, "Crystal River Nuclear Plant Site-Specific Environmental Policies, Permits, Registrations, Certifications and Plans";

also add FLA016960, "CREC Industrial Waste Water Permit";

5 B4.12, I would reword section on waste Included water requirements to include reference to existing procedure SP-736K, "Reactor Building Hydro Demolition Release to the Settling Ponds".

6 B.6.5. typo on page 14; 2 nd paragraph, Corrected 5 th line down, change "10" will only be allowed only at the", to "10" will only be allowed at the" 7

Sections B.4.6 and B.6.6 (2 sections), it Incorporated and added additional needs to be clarified in both locations that installation prerequisite step "discharge" of the water cannot go to the settling ponds until samples are cleared by RP. Prior to clearance, hydro-demolition can proceed as long as the water and rubble are collected in temporary basins / tanks etc. (This is the same approach used during the SGR hydro-demolition.)

8 Section B.6.6, under 'Water Corrected requirements"; 2 nd sentence; revise:

"have been successfully used in the past by CRS to satisfy.." to "have been successfully used in the past by CRS and CR3 to satisfy..".

Same section and paragraph, 3 rd Corrected sentence: During the SGR hydro-demolition, no existing plant piping was utilized, due to reliability concerns. I suggest removing this option since the temporary piping option was very successful.

9 D.2, Installation Requirements, Added Prerequisites, suggest adding the following: "Use of chemicals for this activity are subject to the requirements of CHE-NGGC-0045, NGG Chemical Control Program."

10 Add a prerequisite to ensure that proper Added dikes are setup around equipment, especially chemical storage in accordance with WP-106, "Storm Water HOO Reviews Page 11 of 25

PCHG-DESG Engineering Change 0000075219RO Discharge from Diked Petroleum, Chemical, and Equipment Storage Areas" Li'censinq Pre-DRB3 Design Review Sid Powell 11/28/10 no 1

B.4.1 - Discussion should focus on Reworded B.4.1 remaining in No Mode during this activity.

References to LCOs and Required Actions are unnecessary.

System Engineering I EC 75219 Final Review Scot Stewart I Penetration Sys Engineer I1/29/10 INo Item Co n

Res 1

Drawing SK-75219-CO01 -

Drawing SK-75219-CO01 has been revised, please see latest revision.

Typo in Note 3, "AMY" should be "MAY" Typos in Note 4,

1. Hydrodemolitiondamage should be Hydrodemolition damage.

2. Responsiblecivil should be responsible civil

3. "edces" should be "edges"

4. "descetion" should be "discretion" IWE/IWL EC 75219 Final Review R. Portmann IIWE/IWL 1/29/10 No 1

Need to add the addition of temporary Sump pumps SDP-3A and SDP-3B have Tendon Gallery Sump Pumps and to tag been addressed as well as the need for out SDP-3A & SDP-3B during temporary sumps in the tendon gallery.

hydrodemolition activities 2

Section B, B.4.10 - States that cutting of Design Input B.4.10 reworded.

tendon sheaths in not allowed. Be prepared to revise the EC during hydrodemolition if it occurs. It also states to remove tendons from known flexible sheaths, this I believe is a risk that needs to be discussed and decided in work HOO Reviews Page 12 of 25

PCHG-DESG Engineering Change 0000075219RO order space. May want to consider deleting it from the EC since we are orderinq spare tendons.

3 Various locations reference ACI 503R for THE ACI and ICRI requirements for surface conditioning, have we validated surface preparation meet or exceed the the surface condition requirements of original requirements as outlined in Spec CR3-C-0003?

Section 3.3 of CR3-C-0003. An additional note 5 was added to SK-75219-C001 to slope the top of the removal area to allow the escape of air as described in 3.3.4 during placement. The reference has been added to Section B.

4 The IWL Repair/Replacement plan does These documents are above and beyond not reference ACI 503R or ICRI 03739 for normal IWL requirements. Additional use in the repair. Have we made these testing as described by this documents required documents? If so then the IWL would merely give additional assurance of RPE needs to authorize this via the R&R sound repair without adversely impacting Plan in EC 75218.

the information contained within the IWL repair plan.

5 67T L

Sectations EC 75219 100% review S

- _ _0 e

y_" eOperations SRO 101/30/10 No S ection B, Page 7 - States to remove Design Input B.4.10 reworded.

tendons from known flexible sheaths, I have been lead to believe that they may be left in place at risk and that spare tendons have been ordered.

2 Section B, Page 15 / 18 - in the Section B.6.16 has been rewritten to discussion on thermal monitoring, the incorporate the latest monitoring plan as information to be gathered was revised by described by EC 75218.

the PE engineering team. The existing criteria is for continuous monitoring of 2" subsurface and the inner liner temperature. These are the locations that the 7 day rolling average are based.

Other locations (outside air temperature, 6" and 12") are monitored for use in evaluating changing conditions and other capability for measurement will be in place for local determination of internal concrete temperature as needed.

Redundancy is incorporated into this plan to allow continuous monitoring with potential instrument malfunction or 1-100 Reviews Page 13 of 25

PCHG-DESG Engineering Change 0000075219RO physical damaae durina EC activities.

3 Z05RO - This text is an early exchange of Attachment Z05 was made intentionally monitoring and control ideas / plans that blank. Requirements for monitoring are should be updated per the note above, described in evaluation section, reference An accurate description can be copied to attachment Z05 has been removed.

from EC 75218 4

Z060RO - The test instruments originally The thermal monitoring has been proposed are not being used. I would rewritten in Section B.6.16. It assumes consider deleting this attachment and just that this thermocouple or another similar refer in section B to a methodology as device may be used. To prevent affecting approved by PE engineering within the readability of the entire document, the bounds described, attachment will remain as the evaluation assumes any other device may be used at the discretion of engineering.

5 67 Design Basis Analy EC 75219 100% review John Holliday Civil/Structural 01/30/10 No 1

Section B.2, Fu paragraph: Change EC Paragraph correctly references EC 75218 72518 to EC 75218.

as prescribing the detensioning requirements.

2 Section B.4.10: State those tendons that Input B.4.10 reworded. The intent is for have to be removed must be ram SGT to leave tendons in sheaths and detensioned, coiled, and identification perform removal. Spares have been clearly attached to the tendon. Are these ordered, so any damage to a flexible tendons going to PSC for refurbishment?

sheath would require the tendon be Where is the repair detail for the tendon removed and replaced vs. removing a ducts? Has material been ordered for the much larger number of tendons which repair? Will PSC have sufficient grease if may or may not be damaged. Repair additional tendons are removed? Have details for tendons, grease, anchor we ordered replacement anchor heads?

heads, etc. are outside the scope of this Engineering Change.

3 B.4.14: The EC should state what the B.4.14 reworded. Minimum Splice is splice length is for the #8's. Are the mentioned as 7". Installation sketch will splices going to be staggered, if so adjust require a minimum of 9" with no the cut lines for the existing #8s maximum which will allow for either lap accordingly.

splicing or splicing under the direction of EC 75220.

4 B.4.15: The thermal gradient will be Deleted monitored so as to maintain the delta as close to zero as possible based on a rolling 7 day average. Delete reference to the controlling within 10 degrees.

5 B.4.28: State that the hydrodemolition Incorporated equipment must be enclosed within an HOO Reviews Page 14 of 25

PCHG-DESG Engineering Change 0000075219RO enclosure that is designed to capture all loose debris resulting from hydrodemolition, i.e. high strength netting.

6 Is the equipment hatch going to be Additional precautions were added into installed during hydrodemolition. If not, installation section along with the tagging what precautions are going to be taken to of the tendon gallery sumps.

prevent water from going into containment?

7 B.4.12: Discuss requirement for adding Added requirement and evaluation if hydrochloric acid. Refer to EC 63016.

B.4.6 and B.6.6 as was captured in EC (Evaluated effects on control room 63016. Hydrodemolition vendor has not habitability). Has sufficient acid been yet been finalized (Mac & Mac is still ordered?

under negotiation). Acid would have to be ordered at the discretion of SGT once all contracts are completed.

8 Page 15, Thermal Loads: Delete all Incorporated.

reference to historical records and 60 and 70 degree temperatures. State that "Operations will use the RB ventilation cooling, heating and purge system per OP-417 making daily adjustments as required to maintain the delta as close to zero as possible based on a 7 day rolling average".

9 B.6.16, Temperature Monitoring: 1 st B.6.16 has been rewritten based on the sentence, delete "based on an inside latest revision of EC 75218.

temp of 70 and an outside temp of 60.

Re-write the rest of this section based on EC 75218 Section B.6.10.

10 D.2, Removal of concrete, #4: Are you Paragraph has been reworded based on going to use standard lap splices? If so, the known requirements of EC 75220 at need to re-word this paragraph.

this time. A minimum of 9" tails are required with no maximum to allow for staggering as based on splice details per EC 75220.

11 D.2, Thermal gradient monitoring: Re-Thermal gradient monitoring has been write as described in EC 75218. Delete reworded based on the write up in EC reference to 10 degree delta. Monitoring 75218.

is to maintain a delta as close to zero as possible. Contact engineering is it is 8 degrees.

12 Parts list: Tendon grease, anchor heads, This as a whole will be addressed in EC shims, longer cans, contingency for 75220. This EC requires SGT to consider tendons to be removed due to flex potential damage to tendons that could conduit, or will this be addressed in result from excavating through flexible concrete placement EC?

tendon sheaths.

13 Add a Caveat that work cannot begin until A caveat was in place, however the the root cause (PII) has established decision was made to remove this caveat whether hydrodemolition was a after discussion with P11 and engineering HOO Reviews Page 15 of 25

PCHG-DESG Engineering Change 0000075219RO contributor to the original delamination. If it is, this EC must be revised to address any concern raised by P11.

lead (P. Fagan). It is understood that the portion of the root cause dealing with micro-cracking was reintroduced.

However, after careful discussion, P11 acknowledged that methods for surface preparation other than hydrodemolition could also cause micro-cracking at a much higher frequency. Based on the necessity for surface preparation, hydrodemolition was left in as the least likely to produce adverse affects. A root cause review was added to the EC package to ensure all additional requirements before releasing hydrodemolition for work.

14 I believe there is a strong possibility that the crack may propagate due to vibration at the perimeter of the delamination if hydrodemolition is allowed within several feet of the outer edge of the delamination.

Once the hydrodemolition is past the #8 rebar cage, this problem is probably greatly reduced due to the condition of the concrete (badly fractured and broken). I was under the impression that P11 was going to address this during their root cause evaluation, it now appears that this may not be so. If hydrodemolition is allowed to progress to the edge of the delamination then there should be a discussion in the EC concerning the associated risks, i.e crack Drooaaation.

Additional wording was added to B.6.5 about possible risks of propagating crack into buttresses and equipment hatch concrete. Description of saw cutting was added as one mitigating strategy.

Additional wording concerning risk acceptance based on best engineering judgment using industry guidance was also added.

15 Add requirement to map cracks around Mapping activities added to surface the opening that result from tendon preparation section of installation section.

detensioning as required in EC 75218 I

i~tle ln-r-

_EC 7519 Fia-Rve GlnMxelISG Intle 1/91 SNS 1

B10 - Remove tendons that have flexible Section B.4.10 has been reworded to say duct. Can we distress the tendon, leave it removal of tendons is now at the in the sleeve, remove the concrete, then discretion of SGT. Damaged sleeves will evaluate the sleeve? The depth of the require replacement (not in the scope of concrete removed will vary. The removal this EC) as needed. Spare tendons may of the tendon afterwards will not be a be used or the tendon sent for HOO Reviews Page 16 of 25

PCHG-DESG Engineering Change 0000075219RO problem if it is damaged. For reuse of the reconditioning again at SGT discretion.

tendon even if done prior to demolition, it would have to be sent to PSC for reconditioning. (Jim Clayborn 208-680-6592) 2 D2 - Removal of concrete. 2. States 4" It is understood that some sections may max on demo - Note that delamination "chunk" and separate out sections may come out larger than 4".

(Jim Clayborn 208-680-6592) 3 This EC does not speak very much about The installation instructions now account cutting reinforcing or the need for for this based on the requirements of staggered mechanical or welded rebar interfacing EC 75220. Per our discussion, splices. During the course of concrete a note was added to notify PGN design demolition it would be prudent to consider engineering of the need to cut any rebar that some reinforcing will have to be cut, other than the #8 for further evaluation especially in tightly congested places at and disposition.

the bottom and top of the affected area.

(Jim Clayborn 208-680-6592) 4 Section B:

Acceptable amount depends on the

5. The 10" depth removal maximum limit underlying surface conditions. This is why has some conflicting requirements.

sounding is required with a hammer, etc.

Should give acceptable amount past the as described by ASTM 4580. Any 10" limit.

degraded concrete shall be removed at

5. Should have method to address wind the discretion of the responsible PGN loading if it goes into hurricane season.

Civil Engineer. This is specifically

26. Does EC 63020 cover all de-described in the Installation Section.

tensioning work? (Larry Davis 704-618-2568) 5 Section D:

See resolution above. The preparedness Same comment as above for 10" removal of SGT for potential actions required for limit.

thermal gradients is at their discretion and SGT will need to be prepared for required outside of the scope of this EC the 100 Delta-T contingency (heaters within monitoring of the 7-day average tented area). (Larry Davis 704-618-2568) temperature is already being performed.

Operations is required to adjust the containment interior temperature under OP-417.

6 50.59 Screen:

Please reference REG AR 377913377913for 11 a discusses stress relief cuts, should final 50.59 Screen. Draft has been also address including concrete/rebar removed from EC folder.

removal.

(Larry Davis 704-618-2568) 7 Z05:

Attachment Z05 is now intentionally left Acceptance criteria given is 50 F, EC blank. The monitoring requirements were gives limit as 10°F. (Larry Davis 704-618-updated in the evaluation section as was 2568) required in EC 75218. The installation section also incorporates the latest monitoring plan.

8 SK-75219-CO01, Rev A:

Please see revised Sketch in Section See comments above for acceptable GO1.

HOO Reviews Page 17 of 25

PCHG-DESG Engineering Change 0000075219RO depth. Drawing notes centerline of hoop tendon.

Drawing needs to specify removal area from specific reference points so that cut lines can be laid out by SGT Field Engineers.

Recommend extraneous information be deleted from drawing for clarity.

Should provide contour requirements at top to allow concrete pour. This may also apply to containment opening.

Reference dimensions need to be specified.

(Larry Davis 704-618-2568) 9 Sketch G01RO SK-75219-CO01 Please see revised Sketch in Section

<< Typos in Notes 2, 3, and 4 >>

GO1.

10 Note: Testing requirements throughout Any necessary mock-ups may be EC are beyond the typical requirements completed at the discretion of SGT that SGT performs regularly. Extra time will be needed for planning, mock-up, implementation, etc.

11 ASTM D 4580 is not applicable to this Procedure B of ASTM 4580 is quite project. The sounding equipment and grid applicable. The intent is to use the layout cannot be achieved through rebar instructions contained in the standard as for obvious reasons. (Paul Gosselin xt a guide for using a hammer to sound 1824) concrete after the major delamination is removed. This will ensure no secondary pockets of delamination remain in the wall before concrete replacement.

Civil/Structural/RE EC 75219, Revision 0, final review C. Glenn Pugh Civil/Structural/RE 701/2-8/10 N

S te-co m

mS_

A7 1

PassPort Screen has "outage" checked The outage checkbox is grayed out and no. It should be checked yes will not allow to be checked. This is the same as EC 75000.

2 Under Section B.3.8 add EC 63020 for Added Safe Load Paths 3

Under Section B.4.7 add EC 63020 for Added Safe Load Path when using the Manitowoc 2250 crane 4

Section B.5 has no assumptions or A caveat was in place, however the caveats noted. However, the Risk decision was made to remove this caveat assessment, Section B.6.5 and other after discussion with PII and engineering sections indicated the root cause needs lead (P. Fagan). It is understood that the to be completed prior to start of work.

portion of the root cause dealing with Need to indicate this in the Assumptions micro-cracking was reintroduced.

HOO Reviews Page 18 of 25

PCHG-DESG Engineering Change 0000075219RO section, check the caveat box on the PassPort screen. Agree, that hydro-demolition needs to be ruled out as a contributing cause, or at least justifiy that no further cracking into the buttresses is expected due this method of removal.

However, after careful discussion, P11 acknowledged that methods for surface preparation other than hydrodemolition could also cause micro-cracking at a much higher frequency. Based on the necessity for surface preparation, hydrodemolition was left in as the least likely to produce adverse affects. At this time the additional testing for subsurface microcracking was included. A root cause review was added to the EC package to ensure all additional requirements before releasina hvdrodemolition for work.

5 Under Section B.6.7 add EC 63020 for Added Safe Load Path when using the Manitowoc 2250 crane. This would apply if a chipping platform is reinstalled. Also would apply for hydro 6

Section B.7 needs to be revised to show Updated current project team and interfaces as outlined in Aaron Mallner's email dated 1/26 and as amended by Emin Ortalan's email dated 1/27/10 7

A comment from 30% challenge was to B.4.10 was updated to leave the removal consider the need to pull back the of tendons at the discretion of SGT based tendons from the flexible tendon sleeves on various comments. They shall be because of possible damage from the responsible for ordering replacements as hydro-demolition process. There are no required for this at risk activity.

instructions in the EC to do this.

8 Currently Section D.2 and the sketch Rebar Tail is now specified as 9" says to cut all #8 bars leaving an 8" (+/-

minimum based on Scott Mawhinney's 1") tail. Conversations with installers input. No maximum is provided as cuts indicate they would like an option of are to be made with respect to interfacing leaving more of a tail if possible to do lap EC 75220 with consideration given splices instead of mechanical splices, adjacent rebar, tendons. Lengths are Need to have an option of 8" or 40" specifically called out as potentially (40db) See AREVA comments below for needing longer than 9" based on further information on this staggering and code splice requirements.

9 It appears the "Subsurface Mirco-Based on conversation with P11, it was Cracking Test" per ICRI 3739 is a pullout determined a test should show whether test for repaired concrete. Should this significant micro-cracking would occur in test be in EC 75220 instead of this one?

the subsurface. This test would require pullout of in-situ cores. It is understood that this intent of the test is to normally test across the layers of repair, but this EC implements it a little differently to check the soundness of the underlying concrete. The instructions for use are the same as it would be for checking a repaired surface and is cleaner than HOO Reviews Page 19 of 25

PCHG-DESG Engineering Change 0000075219RO creating a new test. It may also be implemented in EC 75220 for further evaluation of the repaired conditions.

10 Section E.1 has the in-situ strength test See above resolution which is the same as above. Same question, should this be in 75220 instead.

11 30% Comment 11 from Bill Alumbaugh is See Comment #8 resolution similar to comment 8 above and is not included in Section D.2 12 Consider deleting Sections J.3 and J.4.

Deleted Not used 13 The ACI 503R-93 included as an The document has been scanned in attachment has no EC, Attachment, or again and appropriate header added.

page number identification required for an EC attachment.

Dicpie/rga Reiw---

Bc-p _ o'Re-s v-ew Scott Mawhinney 01/28/10 N

(AREVA Engineerin CvlSrcua reieplaese aetreiin General comment on SK 75219-C001 1 Line weight in color do not print as a hard Drawing SK-75219-C001 has been solid line revised, please see latest revision.

2.

Why is the first elevation call Fig. 3 when Drawing SK-75219-COO1.has been the second elevation has no Fig.

revised, please see latest revision.

identification?

3 No ledged for concrete removal limits Drawing SK-75219-CO01 has been revised, please see latest revision.

4 Hatch pattern comes all the way to the Drawing SK-75219-CO01 has been buttress; it should stop 6" before buttress.

revised, please see latest revision.

5 Extraneous delamination information Drawing SK-75219-CO01 has been should be removed from the second revised, please see latest revision.

elevation view and the hatch pattern should cove the entire area (less dense pattern).

6 The "construction opening section should Drawing SK-75219-CO01 has been be called B-B and shown on the elevation revised, please see latest revision.

view; also a 90 degree cut should show a similar detail.

7 The 8" plus or minus 1" is not generous Drawing SK-75219-CO01 has been enough, the book says 7" min for # 8, I revised, please see latest revision.

would say 9" min and add a note to say that I

I HOO Reviews Page 20 of 25

PCHG-DESG Engineering Change 0000075219RO splice must be planned around obstructions such as horizontal tendon ducts, length will vary. Also it is my understanding that near the "dog house" the #8 @ 12" transition to

1. 11 @ 9". Therefore, # 11 will require more than the minimum 7".

8 Section A-A should not say 10" max Drawing SK-75219-C001 has been removal, it should say 10" typical, see note revised, please see latest revision.

3 9

Section A-A please show center line of Drawing SK-75219-C001 has been buttress for clarity and the buttress itself is revised, please see latest revision.

not drafted in the proper proportion.

10 Detail A, I thought 10" deep was to the Drawing SK-75219-C001 has been centerline of hoop tendon, it is not show revised, please see latest revision.

that way. Also surfaces should be shown rough and delineated "see EC 75220 D.2 "preparation of concrete surface" Section D Comments 13 In Section D.2 add:

If a survey is required prior to and just

13. Conduct survey before detensioning, after detensioning it needs to be included after detensioning, and establish in EC 75218 which implements work construction control so that formwork can around the detensioning schedule. This be properly placed so as to verify required EC assumes all that work is completed minimal membrane thickness as well as the and work is ready to commence on the alignment of reinforcing steel.

removal. Please contact Ken McEwan to incorporate this EC comment as needed into EC 75218.

14 Removal of concrete

[below is also note 1 on drawing C001]

1. SK-75219-CO01 depicts the Additional wording was added to step, approximate limits and depths of however, no specific tool weight shall be delaminated concrete, limits of specified based on, the variety of unsound concrete will vary, potential circumstances which may arise.

however, limits of concrete removal ICRI documents recommend no greater are expressly shown. When than 30 lb equipment to prevent micr-unsound concrete is discovered cracking. As such it is left at the beyond the limits of removal the discretion of the RE using the Concrete Responsible Engineer shall be repair manual as a guide.

contacted prior to its removal. In certain areas/circumstances hydrodemolition shall be discontinued and hand methods of removal shall used with chipping tools less than 60 pounds in weight.

[see note 4 on drawing C001]

2. [last part of section], add the word Added "horizontal" hoop tendon

3. when spalled areas pass beyond Added the 10" depth, refer to note 1 and I

HOO Reviews Page 21 of 25 JI

PCHG-DESG Engineering Change 0000075219RO hand methods may be required to complete the removal of unsound concrete.

4. Within 36 & 80 bar diameters of the concrete removal limit reinforcement may be cut to utilize a lap splice

[alternate splices] or. the bar May be trimmed no closer than 9" from the edge of demolition for the use of an approved mechanical coupler. The saw cut/friction blade reinforcement removal is the only recommended preparation for the mechanical coupler installation. However, for safety reasons, flame cutting within 6" of a prepared end is permissible.

The only reinforcement that may be cut and spliced are #11 reinforcement and smaller. Also only # 8 reinforcement and smaller may utilize a lap splice of a minimum of 36 bar diameters.

[Revise note 2 on drawing C001]

Reworded.. Holdpoint was incorporated to prevent cutting of rebar greater than

1. 8 without prior approval to ensure proper lengths will remain in place.

Reference to EC 75220 is also added.

15 1 Preparation of Concrete Surface

1. I would suggest saw cut between 1" and 1 1/2" deep, they should saw cut vertically 6" away from edge of 6"

2. no comment

3. no comment

4. this should go in the category below

5. rebar inspection and preparation of the splice should either be its own section or omitted from EC 75219 and placed in 75220 Saw cut is only prescribed method now.

Drawing shows 6" offset No resolution req'd No resolution req'd Cleaning is part of the surface preparation and is acceptable in the current section. Testing will not commence until all surface prep is completed This inspection is a cursory review by site engineering to ensure any significant issues are identified up front before IWL inspections take place per EC 75220.

This is above and beyond what is required and is able to commence while the civil engineer is already up on necessary work platforms overseeing sounding/surface prep.

16 Surface test

1. no comment [N/C No resolution req'd

2.

N/C No resolution req'd HOO Reviews Page 22 of 25

PCHG-DESG Engineering Change 0000075219RO

3.

N/C

4. Call out the epoxy brand

[General comment: this test should be performed now to make sure it is successful, due to the relative lack of tensile strength of this concrete (aggregate) as compared to other mix designs you may want to verify the test is achievable]

No resolution req'd Epoxy procured is at the discretion of SGT. It was left open with the BOM requiring minimum characteristics so whatever was quickly attainable could be ordered.

Mock-ups are at the discretion of SGT. This testing is again above and beyond what is required by IWL for concrete surface preparation and may be discontinued at the discretion of the responsible civil engineer based on circumstance.

Dicpie/rga Reie Scp of-Revie Mech. Maint.

EC 75219 Final Review Reiee D

-isciplinea-i Rick Pepin 1/30/10 No 1

Section D.2, #4 - remove AI-1000, SGT Added "or approved SGT equivalent" to is not using this procedure, they have ensure traceability of any potential their own procedure (say lAW approved procedure usage, even potentially outside procedure) of SGT's current scope of work.

2 D.2, #5 - Scaffold is lAW approved Added "or approved SGT equivalent" to procedure ensure traceability of any potential procedure usage, even potentially outside of SGT's current scope of work.

3 Removal of Concrete, #4 - Rebar cannot Saw cutting is required for using the be saw cut in many areas, do not use this mechanical couplers based on discussion restriction, we are guessing by drawings with the EC 75220 responsible engineer.

on the rest of this line and we cannot put Added wording to say to contact PGN the "shall not" in here because we may civil engineering for acceptable have issues, leave more should and as alternative methods within the bounds of allowable and not "shall not EC 75220 (in-development) so as not to invalidate the rebar replacement design.

4 Preparation of surface, #1 - I think the Wording changed to PGN civil design "responsible Engineer" making all the engineering. Civil engineering will be field decisions is a hold that we are staffed on dayshift/nightshift with setting ourselves up for. The RE will not mandatory turnovers once work has be here round the clock. Field Engineers commenced. There will be no "sitting on will be. We need to be careful of titles so hands" while waiting for the morning. At when we go round the clock I am sitting least one civil engineer will have received on my hands waiting for the next dayshift.

turnover about the previous shifts work and can direct work in the field as required.

5 Preparation of surface, #5 - Sounding will There seems to be a general be done by "who and who will make this misunderstanding of the sounding contract, is this team around the clock process. Sounding in this case refers to HOO Reviews Page 23 of 25

PCHG-DESG Engineering Change 0000075219RO group that can support a restart of a unit that is off line. Is this group properly staffed to do this work in a schedule basis?

hitting the wall with a hammer or other long metallic object and listening to a tone change. The tone change indicates an area of delamination that needs to be removed. The intent is to remove secondary delamination that is not visible to the naked eye. ASTM 4580 was added to provide guidance on how this works (See procedure B, ASTM 4580). No special equipment or personnel is required.

6 Section B.6.6 Water requirements The samples for radioactivity are clear to us. The base line chemical requirements to us are not clear for what is required for hydro blasting. We need to ensure disposal requirements and waste water but on up front requirements that are not real clear here.

Waste water requirements I believe we can deal with.

These requirements and associated evaluation are exactly as per EC 63016 when Mac & Mac provided the hydrodemolition services. If Mac & Mac is again the hydrodemolition vendor, then they would best know what works with their equipment. This EC was generalized based on the final hydrodemolition vendor being unknown (Be it Mac & Mac or American Hydro). More specific requirements can be included if and when they are required as determined by the vendor. As noted in the EC the details for the water supply are outside the scope of this EC and may be processed in the associated WO task as was the case with EC 63016.

7 Surface Testing Considerations:

Pre statement. "Testing will be implemented under the direction of the RE." How do I schedule that?

1. If this testing is a standard procedure I suggest referencing We can go a long ways doing this testing without putting in concrete, This section is not able to schedule or deliver to the vendor the extent of what is going to be done, somehow we have to better define what we are looking for here, "...To ensure significant damage has not been sustained..."

Wording changed to under the direction of PGN civil design engineering. EC's do not prescribe how work is to be scheduled, they merely provide the design requirements for any given project and why they are acceptable.

Attachments Z03 and Z07 give step by step instructions on how to perform the testing. A brief overview was written in the installation instructions so as to prevent rewriting the ICRI documents in the installation section. For the surface testing, assuming 50 tests are conducted scheduling would be the time it takes to "glue" 50 1 in2 aluminum T-bars to the wall and pull them off. Once the pull of rig is developed it will not take more than a few minutes to conduct a test at each location plus the time to access those locations.

The frequency now includes a practicality statement, however 50 would be the most one should expect. As for the subsurface HOO evies Pae 24of 2 HOO Reviews Page 24 of 25

PCHG-DESG Engineering Change 0000075219RO testing a maximum of three 2" cores at least 6" deep spaced evenly over the entire repair area would be needed" those cores stay in place during testing and again pull as before on the cores. As noted above, PGN civil engineering will be working day/nightshift to support any and all work in the field. Mock-up testing can and should be scheduled/performed at the discretion of SGT. There would also be PGN civil support as required durina that time.

+

+

8 No less than two and no greater than 12.5, the rest of this needs to go Only pH sampling will need to be performed as a

ore-reouisite for discharge. Contractor should strive to keep the pH between 6.0 and 9.0.

Periodic sampling of pH will be needed. A "stop job" limit shall be established at pH less than or equal to 2, or pH greater than or equal to 12.5.

Again, these are the requirements directly related to hydrodemolition work performed under EC 63016 by Mac &

Mac. The requirements states the contractor "should strive" for those limits based on previous SGR experience.

Merely asserting that the contractor should strive for those limits does not prevent the job from being implemented.

As such, the requirement will remain as written as changing the wording does not Drevent work in the field.

9 The surface prep is pretty unique and As noted, these are in-situ tests meaning might end up being a huge point of it is field testing, not lab testing. It is discussion, the manual referenced notes understood there are a number of no embedded materials in the technical construction aids, but the vast majority of guidelines for in-situ testing referenced, the testing is at the surface on a very there are many construction aids in our localized area < 2in 2. The instructions wall that might prevent us getting good allow for testing to be ceased based on samples, not sure how we are going to practicality or if the results show meet this lab testing requirements on the consistent meaningful data. Reference wall.

comment #7 resolution.

10 There is a lot of detail that is based on lab Review comment #7 and #9 resolutions.

testing and lab practices referenced that A practicality statement was added to the will most likely not apply to work that is installation instructions for such cases as taking place on the wall. The pull off test was described. A statement allowing and the surface requirements and amount termination of testing of detail for lab testing may not be applicable on most places on the containment. The amount of steel down by the doghouse and the bottom of the delamination will preclude most of this testing.

11 12 13 14 HOO Reviews Page 25 of 25

PCHG-DESG Engineering Change 0000075219RO 1.1 Design Verification (Select, copy, and paste the table below into a WORD file and e-mail to Lead DV. Select, copy and paste table from DV response below. Have Lead DV agree that all comments are resolved prior to advancing EC status to H/APPR.)

The signature of the Lead Reviewer records that:

the review indicated below has been performed by the Lead Reviewer; appropriate reviews were performed and errors/deficiencies (for all reviews performed) have been resolved and these records are included in the design package; the review was performed in accordance with EGR-NGGC-0003.

Eng.ineersm 1i~ngReviewv~

M we'sRve IScope of Reie EC 75219, Rev.0 1

tecuon A.0, t'age j: uoncrete memovai (EC 75219): In the scope it indicates that this EC will review the necessary work platforms associated to perform the work.

There is no discussion in the EC in Section B or Section D about the work platforms. Need to provide information on the work platforms. Also in the last sentence under this title change "slab" to "delaminated concrete".

vYOrK piatrorm usage nas yet to De finalized. Once all necessary platforms are identified they may be included in a revision to either this EC or EC 75000 under the direction of Paul Fagan.

Changed wording as noted. Currently, only the tendon platforms are identified as being used for repair activities which were qualified previously for work per EC 63016.

2 Section A.6, Page4: OE 14720: It is Included as a requirement of the pre-job mentioned that a note will be added in brief precautions and limitations. that the containment coordinator to inform all personnel in the immediate area about the start of hydro-demolition. This instruction is not in Section DOO.

3 Section A.6, Page 5: OE 29756: Under Included as a requirement of the pre-job how the issue is addressed in this EC, it brief is mentioned a note will be added in precautions and limitations installation instructions regarding proper inspection of the hydro-demolition equipment, however it is not mentioned in DOO Section Precautions and Limitations.

4 Section B.2, Page 1: in the second Sentence correctly reads "75218" paragraph 72518 should be 75218.

In the fourth paragraph add concrete after depth of.

5 Section B.3, Page 1: References ICRI 100 DV Page 1 of 7

PCHG-DESG Engineering Change 0000075219RO 03730, 03732, 03737, and 03739 are now called as # 310.1R, # 310.2, # 310.3, and

1. 210.3. I do not have the revised copies.

I do not know if any information has changed. Suggest adding these numbers in parenthesis. Also note that ACI 515.1R referenced in ICRI 03732 has been withdrawn on Jan 01, 1979.

Reference 1.11: Change 'to" to "for" and "Bon' to "Bond" Reference 1.14: parenthesis missing before Concrete.

Reference 9.2: Change Amendment #229 to 235 and Revision 73 to 81.

Incorporated as noted.

6 Section B.3: Add the following additional References Added references: ACI 318-63, ASTM 421-65 and 98a, CHE-NGGC-0045, SP-736K, Al

-1816, OP-417, AI-1820, EVC-SUBS-00008, EVC-SUBS-00016, EC ED 59400, EC 75497, EVC-SUBS-00107, EVC-CRNF-00002 and FLAO 16960 at the respective locations. The above references are used in the body of the EC at different places.

7 Section B.3, Page 3, Reference 9.2 Revision Level Updated change Amendment 229 to 239 and Revision 73 to 81.

8 Section B.4.1, Page 4: Delete the LCO Design Input reworded and simplified requirements and rest of the paragraph suggest changing it to state that "during No Mode there are no TS requirements for containment integrity or TS Actions that require containment closure, however the containment should not have catastrophic failure during the applicable design basis loads".

9 Section B.4.3, Page 4: add FSAR Section Added Basis 5.1.1 under Basis.

10 Section B.4.4, Page 5: Add OP-417 under OP-417 added. Note was left about the Basis. OP-417 mentions that the optimum maximum temperature approaching average temperature during full power 130°F based on input from system operation is approximately 1150 F (Page engineer. However normal limit was 8). In lieu of this should we use 1 150F changed to 60-115 0F.

instead of 1300 F.

11 Section B.4.6, Page 6: The last sentence WO was providing reference/basis so in the second paragraph mentions the new WO could be completed. To prevent details for water supply and disposal for confusion, WO order was removed and concrete removal shall be included and Basis just references EC 63016.

approved per the associated Work Order Task and references EC 63016 WO 100 DV Page 2 of 7

PCHG-DESG Engineering Change 0000075219RO 1165094-03 under basis. Note that this work order is closed under EC 63016.

Need to develop new work order task for this work.

12 Section B.4.7, Page 6: Add EC 75497.

Added interfacing EC 13 Section B.4.1 1, Page 7: Discuss about Added as per EC 63016 pumps and piping for hydro-demolition process as mentioned in EC 63016 Section B.4.11.

14 Section B.4.19, Page 8: Add 3.9 to Added Improved Technical Specifications under Basis.

15 Section B.4.26, Page 9: Change "of" to Basis added. Reworded to read more "under" in the second line and add EC clearly.

63016 under Basis.

16 Section B.4.28, Page 9: Need to discuss Added discussion about prevention of debris falling on personnel during concrete cutting or hydro-demolition.

17 Section B.6.1, Page 11: In the first line in Corrected this page change "installation of the cuts" to "removal of delaminated concrete" and add after removed in the second line "and repaired" 18 Section B.6.2, Page 11: In the second Corrected paragraph first line add after "The" "delaminated concrete" and change describe to described in the last sentence and change cut installation in the last line to removal process.

19 Section B.6.5, Page 12: It is mentioned This was based on Input from AREVA that 8 1/22" minimum delamination should design engineering in regards to the be removed to get adequate bond proposed radial reinforcement. ACI 316 development length as per ACI 316. The was corrected to read 318. Paragraph development length is dependent upon was reworded to say this was based on concrete strength and bar diameter.

AREVA design engineering input (Scott Without the radial reinforcement design, Mawhinney). The removal depth is now how is the 8 1/2" length determined. Is stated as a 10" typical removal which ACI 316 the right code number, should it encompasses those design requirements.

be 318, Verify. It is also mentioned in the same paragraph that ACI 316 requirements for clear distance behind newly placed reinforcement should be followed. This clear distance should in front of newly placed reinforcement and also the code ACI 316 should be 318.

20 Section B.6.5, Page 13: First line revise Reworded as follows: Once the majority of concrete has been removed and after ensuring that sound concrete exists beyond the 100 DV Page 3 of 7

PCHG-DESG Engineering Change 0000075219RO removed concrete final surface finishing can commence.

In the fourth sentence add after affixed "to Reworded the concrete surface". Delete separate after bond. After guidelines add as per ACI 503R in the next sentence.

In the second paragraph in the line after (Attachment Z07) change end to top.

21 Section B.6.5, Page 14: Delete the Corrected second "only" in the line that says 10" will only be allowed only.....

22 Section B.6.5, Page 14: Wind Loads: A Note added.

sentence can be added here to say that the wind load is enveloped by the Tornado Wind Loads.

23 Section B 6.5, Page 14: Tornado Wind As described in EC 75218, those areas Loads: The reference to Calculation S10-are acknowledged to have those high 0004 is not correct, it should be S10-stress levels and cracking is expected 0006. Calculation S10-0004 evaluates and considered acceptable. As a result of delaminated and detensioned concrete that EC mapping of those cracks in for dead load including equipment and required particularly above and below the thermal loads. It is also mentioned in this construction opening. That mapping calculation (Page 6) that at the final requirement was added into the detensioned state, some tensile and installation section. Additionally, EC shear stresses around the opening 75218 requires that those cracks be exceed the stress acceptance criteria, repaired with grouting per EC 75220.

This calculation also states that justification of these high-stress areas is outside the scope of this calculation.

Where is this justification provided and this should be referenced to indicate that the containment structure meets the acceptance criteria for thermal loads.

24 Section B.6.5, Page 14: Seismic Loads:

Corrected Seismic loads are addressed in Calculation S10-0006 and not in S10-0004. Revise accordingly in two locations.

25 Section B.6.5, Page 15: Pressure Loads:

Revised Change "Defueled "to "During No mode" since during defueled, it is required to consider LODHR pressure loads.

26 Section B.6.12, Page 17: Waste Water:

So referenced Reference Procedure SP-736K for Waste Water removal requirements.

27 Section B.6.16, Page 18: In the first Reworded entire section based on sentence after prestress add "and aligning monitoring requirements as reduced concrete thickness" and add 0 F written in EC 75218.

after 70.

In the second paragraph it is mentioned The temperature is already being 100 DV Page 4 of 7

PCHG-DESG Engineering Change 0000075219RO that device should be placed 2"-3" inside recorded in this fashion without any the core bore, this may interfere with 2"-3" difficulty. Changing it would describe the of polystyrene that will be used to plug measurement in a way it is not taking the core bore, consider changing the place.

dimension to 3"-4".

In the last paragraph, one sentence before the last sentence add after "outside containment" "temperature greater than 50°F and less than 600F".

In the last line add after "Removal" "of concrete can start and" 28 Section B.6.26, Page 20: After EC 63020 All safe load paths from 63016 were add EC 63016. Since EC 63016 covers included in latest rev of 63020 per E.

safe load paths for movement of Ortalan.

platforms.

29 Section B.6.28, Page 20: Add after may Added.

in the last sentence "be".

I 30 Section D.2, Page 1: Suggest adding the following additional Prerequisites and Precautions:

a) Test all hydrodemoltion equipment before start of work.

b) A safety net or other devices must be erected around the hydrdemolition equipment to prevent debris from falling and injuring personnel c) Ensure that all applicable environmental permits are obtained and in place before implementation of activities associated with this EC.

d) Ensure that activities associated with this EC are in accordance with the applicable portions of EVC-CRNF-0002, "Use of Crystal River Nuclear Plant Site Specific Environmental Compliance Manual" e) All chemicals and other consumables shall be approved and properly labeled per CHE-NGGC-0045.

f) The containment coordinator is to be informed prior to start of hydro-demolition equipment. The coordinator must inform all personnel in the immediate area that the hydro-demolition activities will start and noise levels will increase dramatically.

Additional prerequisites added.

100 DV Page 5 of 7

PCHG-DESG Engineering Change 0000075219RO 31 Section D.2, Page 1: The work order Added.

listed in Item 8 under Prerequisites and Precautions is not identified in X-ref.

32 Section D.2, Page 3: In item 7.b. delete Incorporated exceed after should.

In Item 3 under Subsurface Micro-Cracking Test Considerations, delete "to" after craft and in Item 5 minimum of three times should be three locations, clarify.

In Item 1 under Monitoring... add after attached "to".

33 File G01-SK-75219-CO01: Editorial Drawing has been revised.

Note 1: Change 1CR1 to ICRI and AC1 to ACI.

Drawing 421-032 is the proper drawing Note 3: Change AMY to MAY and and references the layout of the #8 bars.

DISECRETION to DESECRTION.

Note 4: Provide space between Legend and Delamination depth is a HYDRDEMOLITION and DAMAGE.

general guide prepared by the condition Change C to G in third line and provide assessment team. A noted in the space after RESPONSIBLE and change installation instructions, the drawing is to DSCETION to DESCRETION in the provide a guideline/starting point.

fourth line.

Sounding will ensure any are which may Drawing 421-032 referenced in Note 2 exceed the limits shown on that figure are should be 421-351 verify, properly removed.

Some locations that are shown to have delamination depths not greater than 8.5" under LEGEND have depths greater than 8.5" verify.

34 Section H.1, Page 1: Under EC 75219 Deleted scope, delete "and removal" after detensioning in the third line.

35 Section H.2, Page 4: the fifth line requires Reworded some rewording. Should this be plant personnel and Final DRB.

36 Section J.1, Page 1: Job Objectives: Last Incorporated sentence change This to The.

Page 2: Under Error Precursor, suggest checking Repetitive actions, Unexpected equip conditions, Adverse physical conditions, illness and under Error Prevention Techniques "Tests".

37 Attachment Z02: Does not have header Header was added and footer.

38 Attachment Z05, Page 1: change removal Attachment Z05 is now intentionally left to removed in the third line under blank based on it containing outdated Purpose.

monitoring requirements. This was based Page 2: Item 6, delete r from strand in the on review comments by Operations.

first line.

Note: The Lead Reviewer signature on the EC DV milestone panel signifies that a lead review has been performed in accordance with EGR-NGGC-0003 and that errors/deficiencies (for all reviews performed) have been resolved and included in the EC package.

100 DV Page 6 of 7

PCHG-DESG Engineering Change 0000075219RO 100 DV Page 7 of 7

PCHG-DESG Engineering Change 0000075219RO J.1 Engineering Pre-Job Briefing Responsible Engineer:

Aaron Mallner Date:

12/23/09 Job Obiectives: (Clearly define the task and what the task entails (scope). Discuss how the scope of the task was validated.)

The main objective of this EC is to remove the delaminated concrete as documented in AR 358724358724 This will be accomplished via hydro demolition and/or mechanical removal/cutting. Underlying traditional reinforcements will be cut and removed as a result of this EC. Removal method will be such that tendon sheaths sustain minimal damage so their reuse is possible. The end state of this EC shall provide necessary input into the interfacing EC 75220 for concrete placement.

Job Expectations: (Clearly define Roles and Responsibilities (performer, preparer, checker, independence of verifier, project coordinator, corporate, Non Station Personnel, etc.).

Aaron Mallner will act as Responsible Engineers for this EC. A specific verifier, third party reviewer, etc.

have not been identified at this time. Careful interface and oversight by RE and Supervision will be required since this EC will also involve many consultants, contractors, and in-house engineering staff.

Other plant personnel from the Root Cause team, Maintenance, Radiation Protection, etc will have an opportunity to review and comment on the EC package.

Other Expectations include:

Perform evaluations and analysis of acceptable repair options.

Follow applicable procedures.

Maintain communication with assigned personnel.

Review and incorporate applicable OE.

Effectively communicate issues that impact success of product or established schedule.

Notify supervision if conditions change that alter the scope of this pre-job brief or the validation planning. Maintain focus on risk planning established in validation plan.

Target date for EC approval to meet project schedule needs.

Skill Sets Required (including impacted organization reviewers): (Review personnel qualifications. Establish appropriate mentoring and oversight if appropriate.)

This is a civil/structural design modification. Civil/Structural design engineer qualifications are required.

All anticipated personnel assigned to this modification are experienced and do not require mentoring.

CR3 Design engineering supervision and management will provide oversight on the EC.

Specific skill set requirements include:

Knowledge of the ACI Building Code and Concrete Design techniques.

Knowledge of CR3 Design and Licensing Basis Knowledge of finite element plate and beam analysis, and seismic analysis techniques.

Coordination with team members to evaluate ongoing activities Remain cognizant of plant personnel safety during concrete placement.

Knowledge of heavy load lifting activities J00 Page 1 of 8

PCHG-DESG Engineering Change 0000075219R0 Error Precursors (TWIN analysis)

Task Demands Time/Schedule Pressure High Workload Multiple simultaneous tasks Repetitive actions/monotony Unrecoverable / Irreversible actions Interpretation requirements Unclear goals, roles, responsibilities Lack of/or unclear standards r7, Activity inputs inadequate Work Environment Distractions rJ Changes from routine r,

Confusing displays/Controls Workarounds/OOS equipment "j Hidden system responses I

Unexpected equip conditions Adverse physical conditions r-Vague or incorrect guidance Individual Capabilities Unfamiliarity with task

.r Lack of knowledge New techniques not used before Lack of proficiency Unsystematic problem solving skills "Unsafe" attitude for critical tasks Illness/ Fatigue/ General Health Human Nature Stress - Work/ Home Health patterns jy-Assumptions Complacence Overconfidence r7 Mind Set Inaccurate risk perceptions

[7 Mental shortcuts r7 Limited short term memory Apparent emotional health First day back from days off Wo ý First time evolution Error Prevention Techniques W-1 Self Check / STAR r*..i Checklists r-o Peer Check F,.5 Step Problem Solving Process r7 OAQ-3 Pass (Att. 13) p Communication r-f Mentoring Task Planning Review r.i Procedure adherence 17pTests Reviews r-SAFER F Time out Prioritization/Budget Required F1 Yes lNo

[Sponsor identified F

Parts identified Project prioritized & budgeted Elements for estimate identified rT Capital/ O&M 17 Maintenance to implement Contractor to implement Additional Checklist Items J00 Page 2 of 8

PCHG-DESG Engineering Change 0000075219R0 Roles/Responsibilities/Reviews ro Work assignment made, roles defined, key interfaces identified jv Required internal reviews (including an independent verifier), Required third party reviews Jr' Expectations and makeup of EC Teams and DRB rv Individual accountability made clear Plant Interface Plant Walkdown needs I-ALARA rv Personal safety (heat stress, electrical, safety equipment) rV Review plant scheduling and plant interface considerations Product Quality Considerations ro Risk management worksheet and Validation plan completed, mitigating strategies discussed Utilize the Product Quality Checklists r

Formalized design inputs (for Outsourced products and vendor supplied inputs) f Need for a formal FMEA r

For digital upgrades, consider EGR-NGGC-0157 requirements

r.

Design basis and margin considerations identified IV Validating assumptions Human Performance Tools rv Lessons leamed / CE items - Include feedback on recent product quality concerns from CAP roll-up, EPR, EC, Team implementation roll-up and EC reviews [Significant NCR 105197]

For EC (Permanent Design/Commercial Change, Alternate Replacements and Temporary Design/Commercial Change) reviews: Review the last 6 months of NCRs related to Engineering Change by running a text search report using "Engineering Change" or "EC."

Methods of communicating and coordinating actions r

Emphasis on doing the job right vs. schedule Miscellaneous r

Review appropriate programs/ procedures to be used Schedule of milestones (design inputs, reviews, etc.)

f Implementation of work management tool to schedule reviews r

Implementation of project management tools (including need for a project plan) per NGGM-PM-001 8 Comments:

J.2 Engineering Change Checklist The following engineering change checklists address the design specification, administrative items, implementation, and testing. Use this checklist to ensure all important aspects of the engineering change have been captured.

Adminlstralliv/ASSPORT C derawe Y

NA 1

Problem statement is adequately documented in the Contents section of the EC.

r, F 2

Solution statement is adequately documented in the Contents section of the EC. Options are evaluated and the

' 7 reasons for selection and elimination have been provided.

3 The history/root cause of the issue that has necessitated the EC has been provided. Applicable NCRs and OE w

r have been incorporated.

4 EC Team members are listed in the Contents section. An NIT SME has been included on the EC team for plant r

I' J00 Page 3 of 8

PCHG-DESG Engineering Change 0000075219R0 AdministrativelPASSPORT Considerations Y

NA digital SSC-related products.

5 If EC is a Commercial Change, the Commercial Change Screening Criteria (Attachment 1 of EGR-NGGC-0005) has been completed.

6 The revision levels of applicable documents utilized to develop the EC have been verified.

R 7

The accuracy of the Table of Contents has been verified. Ensure page numbers in the Table of Contents match F

the page numbers in the sections.

8 "Track changes", if used, has been set to display revision bars only.

R 9

Validation plan is included in the review section of the EC package (if required).

rF 17 10 DRB comments/resolutions are included in the review section of the EC package

[e-(

11 All information is legible so that QA records can be made.

12 EGR-NGGC-0005, Attachment 7 screening criteria has been used to determine required reviews.

FT 13 The required discipline inputs and outputs have been design verified or engineering reviewed as required. Lead i'

reviews and concurrent reviews have been completed.

14 The applicable Discipline, Program, and 50.59 reviewers are qualified in PQD.

I r

15 If EC is a Master, the Master EC field is checked. If EC is a Child, Child is in the KW4 field and the Master EC is i

R on the Xref panel.

16 For concurrent modifications, the Adv Wk Appvd field is checked.

ni We 17 "Cavet Outst" field is checked if caveats or exclusions (future details, missing documentation, vendor outputs, etc.) are identified in the scope of the EC.

ADL is complete. All affected documents are included. Reviewed field is checked. If a Turnover is required to 18 Operations, the "Ops Svc" field is checked for each document that is required to be updated prior to turnover.

Compare ADL to Section C (Markup) to ensure affected document lists match.

19 For temporary changes, the appropriate incorporation code has been identified for documents on the ADL.

!-W 20 AEL is complete. All affected tags are included. Minor revisions have been initiated and reviewed.

F F

21 Reason for Revision attribute has been added and completed if EC is being revised FT 22 "VALIDATION PLAN APPROVED" and "50.59 APPROVED AND ON XREF" attributes have been added and Fr completed if applicable. Document Validation Plan approvals in notes.

23 The correct quality class has been included on the Attributes Panel in accordance with EDB and the Quality W0 i

Classification of Section B.

24 Turnover to Operations is checked Y or N on the Attributes panel (and agrees with Turnover/Closeout Summary F

and Testing requirements).

25 All required reviews and approval signoffs have been included on the Milestone Panel.

R 1

26 For EC's that require turnover, the 'RE T/O RELEASE' and 'OPS T/O ACCEPT' milestones are included. These 11 R-i milestones are not included for EC's not requiring turnover (including Master EC's). The 'DOC REV RELEASE' milestone is not included for Master EC's.

27 For Child EC's, the N050.59 IMPACT1 and N050.59 IMPACT2 milestones are included.

r-i 28 Work Orders (required for turnover), Action Requests (NCR, OPEX, REG, NTM, etc.) are included in the Xref R

Panel. Delete Work Package and Work Request references. Ensure no WO tasks are on Xref panel for Master EC's.

29 An NTM AR has been initiated if a post-job briefing and/or post-job critique has been specified on the validation R

17 plan 30 A.1.1.

The basis for the initial risk level has been re-evaluated during the Engineering product development F7 process when new information is available, and for modified or new scope.

J00 Page 4 of 8

PCHG-DESG Engineering Change 0000075219R0 Design Section Yý NA 1

Design Specification scope is clearly defined with specific detail and for software applications meets EGR-NGGC-F rF 0157 requirements. Caveats or exclusions that will be included in a future EC revision (e.g. future details, missing documentation, vendor outputs, etc.) are identified.

2 Codes, specifications and standards applicable to the design are consistent with the plant commitments (e.g.

UFSAR).

3 All design inputs identified in EGR-NGGC-0005, Attachment 2 and EGR-NGGC-0157, Attachment 6 have been r

reviewed for applicability.

4 Design inputs indicate the basis and source of each input.

rF_

F 5

Design inputs are in accordance with the sources identified in Attachment 2 of EGR-NGGC-0005.

WI 6

Design inputs clearly address required operating conditions for equipment (normal, transient, and accidents) and r

the expected performance requirements under these conditions.

7 Interfaces with other SSCs are clearly identified in design inputs.

rr 8

All assumptions are clearly identified and bases for assumptions (or method of validation) are provided.

IT 9

Evaluation considers and dispositions each identified design input. Evaluations are provided in the "Evaluation" F

section, and not in the "Design Inputs" section.

10 Impacts on PSA modes, assumptions and success criteria are identified.

rr.

11 Relative internal (plant specific) and external (nuclear and non-nuclear) operating experience is considered in the W!,

F design and is evaluated.

12 Evaluation includes a failure modes and effect discussion for new and modified equipment.

V7 F

13 Evaluation identifies changes to margins and considers mitigation for reduced margins.

W r

14 Evaluation considers in-process Engineering Changes to interfacing SSCs. Potential impacts based on possible F

rF cumulative effects are evaluated. Required sequencing of implementation and document updates is considered.

15 Vendor-supplied technical data has been validated against design inputs.

FIT'!

16 lndividualsNendors who provided input (excluding EC Team members) are identified in the Interfaces section.

F7 r7 17 The applicable quality classifications are identified based on EC scope and boundaries are established.

W IT-,

18 Constructability walkdowns have been completed, if possible, to verify actual plant configuration and Y I F' constructability of the design. Where constructability walkdowns are not possible, the modification clearly identifies the possible risk that field changes based on actual as-builts may be required.

19 Modifications that involve interface agreements have responsibilities (including engineer of record) and testing r

1'-

requirements defined by responsible groups.

20 The impact to Preventive Maintenance program has been considered and reviewed. This includes:

r F

establishing or revising the scope of PM activities, including material requirement changes (Note: Model Work Order may have staged Material Requests that require revision) (PM Planner) establishing or revising the frequency of PM performance (System Engineer or Program Engineer) planning to reset schedule for PM performance based on modification activities (PM Program Manager) 21 Software and databases used meet the benchmarking and verification procedural requirements.

-'! rI7 22 Increased rigor used when modifying daisy-chained electrical circuits. (CAPR 292232)

F, 117 23 Wire segment numbers are changed wherever a discontinuity is introduced or recognized within a control circuit.

WF (CAPR 292232)

Document/Database Impact Considerations Y

NA 1

Design record document (Drawings, Calculations, DBD's, Specifications, etc.) impacts have been identified.

Fr r-J00 Page 5 of 8

PCHG-DESG Engineering Change 0000075219R0 Document/Database Impact Considerations Y

NA 2

Non-Design record document (POM Procedures, System Descriptions, Operator Aids, etc.) impacts have been r1 V,

identified.

3 Vendor Manual changes for addition or deletion of information have been identified.

F r1 4

EDB change information is clearly identified. Review EDB requirements for affected or new equipment tags and F,

P ensure Maintenance Rule and ZTEF codes have been entered. Minimum required data fields for new equipment tags have been included per EGR-NGGC-0012. A Manufacturer Model Version (MMV) has been identified for any procured component subject to maintenance. For calibrated devices, setpoint parameters have been identified. If installing new equipment, consider if an EDB tag number(s) should be assigned. Ensure software components receive EDB tag numbers, when required by EGR-NGGC-0157.

5 Electrical cable management impact has been identified and input provided by the cable management r

17 coordinator if wires, cables or conduits are added, removed or spared.

6 The applicable load lists in Operations procedures are considered for impact if adding, removing, or modifying r-P electrical characteristics of a component fed from an electrical panel, bus or MCC.

7 Markups are provided for each impacted document or a precise description of the impact to each document is F

rP7 provided. Consider preparation of a sketch list to aid in document update, particularly for large projects and when multiple sketches impact the same drawing.

8 Other tracking items (PMR AR's, NTM AR's, etc.) are identified.

I-11 rP,,

9 If the EC is a Master, no minor revisions are created.

F Re I 10 Changes potentially impacting a regulatory commitment (BNP RRIL, RG 1.97, EP, ISI, ASSD, SBO, T/S, etc.) are F

P1 adequately reviewed for updating of the calibration program (Ref. BNP procedure ENP-33.4) [BNP only]

Implementation Section V

NA 1

A succinct description of the EC implementation instructions has been included in the "Installation" section.

1 1

2 The Precautions and Limitations applicable to the instructions are included. Caveats or exclusions that will be f

included in a future EC revision (e.g. future details, missing documentation, vendor outputs, etc.) are identified.

3 Implementation instructions have been written to ensure that design requirements are achieved and maintained r

throughout implementation.

4 The installation instructions clearly identify ALL installation sketches to be used and, encompass the entire Pr F

installation scope of the mod. For software components, installation instructions are provided.

5 For concurrent modifications, the requirements of EGR-NGGC-0005, Attachment 3 have been met.

F 6

For temporary changes, requirements for temporary change tagging have been developed and documented.

rF P,

7 For temporary changes, an expiration date has been established and specific removal requirements have been F

R considered and documented.

8 The EC Parts List includes the necessary parts for.the design, including software components.

P F

9 The "Use" column of the EC Parts List is filled in correctly for the quality class of parts to be used in the design.

r, 10 Elimination of inventory has been considered, including budget impact.

F rI 11 QC Holdpoints currently not included in existing procedures needed for implementation of the EC are identified.

r7rlF Refer to NUA-NGGC-1530.

12 For ECs requiring turnover, a request for the planner to initiate an AD type Work Order Task has been included in r 7W the instructions [BNP only]

13 A Turnover/Closeout Summary is included that identifies:

(for Master ECs) Scope of Child ECs including identification of affected SSCs and boundaries Known activities to be verified in the turnover process, specifically, required Operation's and Maintenance training J00 Page 6 of 8

PCHG-DESG Engineering Change 0000075219R0 Implementation Section 7'Y NA Identification of post-turnover testing requirements Justification if no turnover is required Identification of known exceptions and caveats for turnover Identification of closure activities and schedule Identification of any tracking mechanisms for turnover or closeout activities Spare parts are identified and M&CS notified Testing Considerations Y

NA It has been verified that the test will demonstrate satisfaction of all performance criteria, including software functions, of the modification in addition to verifying the operability of the affected components and systems.

2 It has been verified that the modification will be tested in all its operating configurations. It has been verified that the test determines the modification has not adversely affected the unmodified portions of the component or I system.

3 A.1.2.

It has been verified that the proposed test demonstrates proper functioning of the component or systems over its entire range of operation and can be performed under both current and anticipated plant conditions.

4 The test should verify that any substituted components or equivalency engineering was accurate and complete.

5 It has been verified that modifications to redundant equipment and components are tested identically and that subsequent testing receive the same level of review, verification, and validation as the initial test.

6 If the proposed test will cause plant parameters to change, it has been verified that all administrative and operating requirements are met for the anticipated changes.

7 Responsibility and authority to intervene or terminate the test if problems are encountered during testing have been established and communicated.

8 The test termination criteria are specified. It has been verified that the test termination criteria do not conflict with N

guidance contained in normal, off-normal, or emergency operating procedures. Methods for resolving discrepancies have been identified.

9 It has been verified and documented that any procedure or document referenced by the test procedure is the most current revision.

10 Consideration has been giving to whether or not this test is an infrequently performed test or evolution or requires heightened level of awareness procedures. The basis for this determination has been developed and documented. [BNP - OPLP-017, CR3-AI-550, HNP-PLP-1 00, RNP-PLP-037]

11 If senior managers are required to be present during the test, the appropriate managers and their responsibilities have been identified.

12 It has been verified that station personnel required to conduct the test are trained and qualified to perform the f

test.

13 Post modification testing includes plant mode required for testing and any special requirements.

14 Electrical and I&C post modification testing is specified per EGR-NGGC-0155.

F W

15 If an SSC has been disturbed and then returned to original state, appropriate testing is specified.

1 F

16 If separate testing is performed on different portions of the affected SSCs (e.g., an electrical circuit), the overall r

test plan ensures that no portions of affected SSCs that are required to be tested are omitted.

17 Plant digital SSC-related testing has been implemented per criteria in EGR-NGGC-0157. Software functionality has been validated prior to installation using test systems, simulations, or mockups.

18 A special procedure has been developed for PMT if an adequate procedure does not currently exist.

J00D Page 7 of 8

PCHG-DESG Engineering Change 0000075219RO Testing Considerations Y

NA 19 Post' modification testing includes design parameter/function to be tested and acceptance criteria.

ot rF 20 Failure modes and effects analysis results are used as input to modification test planning and software r

N validations.

JO0 Page 8 of 8

Section ZOO EC 75219 Pagel 1 f43 TECHNICAL GUIDELINES Prepared by the International Concrete Repair Institute January 1997 Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays Guideline No. 03732 Technical Director: Lawrence Hagan Graphic designer: Karen Morey Copyright © 1997 International Concrete Repair Institute All rights reserved.

1323 Shepard Drive, Suite D, Sterling, Virginia 20164-4428 Phone 703-450-0116 Fax 703-450-0119 Email concrepair@aol.com

(

Section ZOO I)

NVEF-NATIONAL CONCRETE REPAIR I N S T I1

) T I-EC 75219 Page 2 of 43 About ICRI guidelines The International Concrete Repair Institute (ICR1) was founded to improve the durability of concrete repair and enhance its value for structure owners. The identifica-tion, development, and promotion of the most promising methods and materials are primary vehicles for accel-erating advances in repair technology. ICRI members working through a variety offorums have the opportu-nity to address these issues and to directly contribute to improving the practice of concrete repair.

A principal component of this effort is to make carefully selected information on critical subjects readily acces-sible to decision makers. During the past several de-cades, much has been reported in the literature on con-crete repair methods and materials as they have been developed and refined. Nevertheless, it has been diffi-cult to find critically reviewed information on the state of the art condensed into easy to use formats.

To that end, ICRI guidelines are prepared by sanctioned task groups and approved by the ICRI Technical Activi-ties Committee. Each guideline is designed to address a specific area of practice recognized as essential to the achievement of durable repairs. All ICRI guideline docu-ments are subject to continual review by the membership and may be revised as approved by the Technical Activi-ties Committee.

Technical Activities Committee Jack A. Morrow (chairman)

Samson Bandimere David Barton Eric Edelson Peter H. Emmons Robert Gaul Robert Gulyas Peter Harwood Ken Lozen James E. McDonald Dennis Pinelle Randall W. Poston Jeff Small Producers of this guideline Task Group Members Rick Toman (chairman)

Wayne Benitz Norm Gill Keith Pashina Robert Traylor Doug Wendler Acknowledgements The members of the task group thank the many ICRI members who, through their review of this guideline, offered helpful suggestions. For their friendly yet rigor-ous critique, we particularly acknowledge the special contributions from the following:

Bryant Mather Sara Ramsdell Richard Reese James Warner Mark Wileczek 7)

)

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 3 of 43 INTERNATIONAL CONCRETE REPAIR N S T

'1 1. 1 S

Contents About this guideline.............................................................................

2 Selecting surface preparation methods................................................

2 M echanics of concrete removal...........................................................

3 Specifying with concrete surface profiles.............................................

6 M ethod selector...................................................................................

7 Method descriptions Detergent scrubbing........................................................................

8 Low-pressure water cleaning...........................................................

10 Acid etching...................................................................................

12 Grinding...........................................................................................

14 Abrasive (sand) blasting................................................................

16 Steel shotblasting...........................................................................

18 Scarifying........................................................................................

20 Needle scaling.................................................................................

22 High and ultra high-pressure water jetting.....................................

24 Scabbling........................................................................................

26 Flame blasting................................................................................

28 M illing/rotomilling..........................................................................

30 Appendix A: Method selection process.............................................

32 Checklist: Substrate conditions.....................................................

34 Checklist: Ow ner requirements............................................................

35 Checklist: Application conditions..................................................

36 Appendix B: Sealers and coatings.....................................................

39 Appendix C: Safety..............................................................................

40 References and related material...........................................................

41 This document is intended as a voluntary guideline for the owner, design professional and concrete repair contractor. It is not in-tended to relieve the professional engineer or designer of any responsibility for the specification of concrete repair methods, materials or practices. While we believe the information contained herein represents the proper means to achieve quality results, the International Concrete Repair Institute must disclaim any liability or responsibility to those who may choose to rely on all or any part of this guideline.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-1

Section ZOO INTlERNATIONAL CONCRETE REPAIR I N S T I T U T E EC 75219 Page 4 of 43 About this guideline This guide provides designers, specifiers, contractors, and manufacturers with the tools needed to select and specify the methods for preparing concrete surfaces prior to the application of sealer, coating and polymer over-lay systems. For the purposes of this guideline, surface preparation is the process by which sound, clean, and suitably roughened surfaces are produced on concrete substrates. This process includes the removal of un-sound concrete and bond-inhibiting films, strength verification, opening the pore structure, and establish-ing profiles suitable for the application of the speci-fied protective system.

Although many of the method summaries included in this document contain data on removal capabilities, a full discussion of methods for the removal of encrusta-tions, stains, embedded contaminants, or existing coat-ings is beyond the scope of this guideline.

Guideline tools 1 Method Selection Process: A workbook designed to organize and prioritize information needed for good selection decisions is located in Appendix A. Sample checklists and examples are included.

2 Method selector: This chart identifies methods ca-pable of producing the profile(s) typically recom-mended for each coating type.

3 Method summaries: Capabilities, limitations, oper-ating requirements, environmental factors, and safety considerations for each method are presented.

4 Surface profile chips: These replicas of typical sur-faces produced by one or more of the methods pro-vide a visual standard for purposes of specification, execution, and verification.

Selecting surface preparation methods Determine project objectives h requirements Most coating or sealing projects will have unique con-ditions and special requirements that must be evaluated to determine which method(s) will best meet the engi-neers' and owners' objectives. The sample checklists may be used to gather data needed to identify and pri-oritize performance requirements (pages 34 - 36). They will help ensure that important issues will be resolved at the optimum time-before the project is underway.

Substrate Coating conditions requirements

{

project objectives Project Owner Application Analysis conditions L Determine and prioritize performance criteria Identify methods which will provide required Preparation performance Strategy Select method(s) that provides optimum balance of performance, risk, and cost factors 1 Substrate condition: The strength of the substrate, and the presence of unsound or bond-inhibiting ma-terials help define the nature and volume of prepara-tion needed.

2 Owner requirements: Noise, vibration, dust, and wa-ter are effects generated by various preparation meth-ods. The owner's need for uninterrupted use of the structure, concerns about operating environment or property damage potential will limit the choices.

3 Material requirements: Surface preparation require-ments will vary with the protective coating system selected. The properties and application requirements of the selected system should be determined before or during this phase.

4 Application conditions Generation of dust, slurries, or water may require con-tainment and safe disposal. Mechanical ventilation, available power sources, the size of door openings, and minimum clearance will affect surface prepara-tion decisions.

)

03732-2 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR'SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 5 of 43 NkI'EFIRNAT ION At.,

to I C CONCIRIETE RIEPAIR All~~~

-TtJr U

Establish performance priorities Performance criteria which best satisfy project objec-tives and requirements are developed and prioritized (see Appendix A, p. 37).

Example: Deck coating installation A parking structure providing 240 spaces for hospital employees is to be protected by a traffic bearing mem-brane. Surface preparation will remove all deteriorated concrete, bond-inhibiting contaminants, and achieve a profile of CSP 3 -4. Structure has a common shear wall with patient rooms for two of its four levels. The hospi-tal requires that 85% of parking capacity remain in ser-vice throughout project.

Priorities: (ranked in order of importance)

I Dust-free preparation to prevent finish damage to parked vehicles 2 Low noise/vibration to minimize patient discomfort 3 Achieve profile CSP 3 or 4 to provide optimum sur-face for bonding 4 Fast turnaround to minimize inconvenience Evaluate surface preparation methods Selecting the method(s) which optimize project objec-tives requires a good knowledge of the available options.

The method selector chart may be used to make a pre-liminary identification of the methods capable of pro-ducing the required surface profiles. The method sum-maries compare data on the capabilities, limitations, operating requirements, and environmental consider-ations for each surface preparation method.

Select and specify surface preparation methods Final selection is based on the relationship between cost, project objectives, and risk. The selection process work-book (Appendix A) provides a systematic framework for organizing project data and assessing method suitabil-ity. More than one method may be capable of producing the desired results. Further, more than one method may be required to produce those results economically. Un-acceptably rough profiles on existing or prepared sur-faces may be reduced through additional passes using properly selected surface preparation equipment. On oc-casion, the application of a resurfacing mortar may be required to achieve the profile and appearance desired.

The nine concrete surface profile chips provide bench-mark profiles to aid in achieving the desired result.

Mechanics of concrete removal In addition to project-specific requirements, method se-lection must also be guided by the following principles of sound practice:

1 The structure to be coated should not be damaged.

2 The reinforcing steel should not be damaged nor its bond with the concrete loosened.

3 Vibration, impact, or thermal loads applied should not weaken the concrete, This section describes the cutting mechanisms used by the methods summarized herein. This information will help users assess the relative potential of each prepara-tion method to damage or weaken the substrate.

Two methods, low-pressure water cleaning and de-tergent scrubbing, do not remove sound concrete and do not noticeably alter the profile of concrete surfaces.

Cleaning is accomplished through one or a combination of the following: the surfactant effect of detergents, the solvent effect of water, and the shearing force of brushes or high velocity water. A third method, acid etching, chemically dissolves calcium hydroxide, Ca(OH) 2 crys-tals and calcium silicate hydrate (C-S-H) which make up the hydrated solids in cement paste. The dissolution of these reaction products causes a slight loss of cement paste, to produce a very light profile on the exposed sur-face. The remaining nine methods summarized in this guideline will utilize one or a combination of the fol-lowing cutting actions.

Erosion Erosion causes the wearing away or progressive disin-tegration of concrete surfaces. Abrasive force applied through grinding with stones, abrasive discs, or blocks with embedded diamonds wears away the cement paste, fines, and coarse aggregate at a uniform rate to produce a nearly flat surface having little or no profile (Figure 1).

Abrasion grinding Figure 1 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-3

Section ZOO jf~ INTERNATIONAL CONCRETE REPAIR

,0 I N S T I T U T IE EC 75219 Page 6 of 43 A stream of water projected onto the surface under high pressure is another form of erosion in which cavitation and the friction generated by water velocity combine to wear away the cement paste. Unlike grinding, water jet-ting will not produce a smooth, uniform surface. As ex-posure to water jetting increases, so will the profile as the softer paste and embedded fines erode leaving be-hind "islands" of the harder coarse aggregate. Under pro-longed exposure to water jetting, coarse aggregate will be undercut and washed away (figure 2). Applicable Meth-ods: grinding, high and ultra high-pressure water jetting.

Pulverization The cutting effect is derived from the collision of small particles traveling at a high velocity with the concrete surface (figure 4). Because the mass of the particles is comparatively small, their impact is not known to pro-duce bruising. Hard, sharp-edged media can produce fast cutting rates. As with water jetting, the cement paste is reduced at a faster rate than is the coarse aggregate. This difference in cutting rate has the effect of exposing and undercutting the coarse aggregate to produce a surface that will become highly profiled as exposure time is in-creased. Applicable methods: steel shotblasting, abra-sive blasting.

h Cavitation (water erosion) high and ultra high-pressure water jetting

)

Figure 2 Impact Several preparation methods strike the surface repeat-edly with hardened points to produce momentary me-chanical loads which, at the points of impact, exceed the tensile and compressive strength of the concrete, causing it to yield. The force of the impact pulverizes and fractures the structure of both cement paste and ag-gregate at and adjacent to the point of contact (figure 3).

Some of the cracks and loosened aggregate may remain leaving a "bruised" layer at the surface. Applicable methods: scarifying, scabbling, milling/rotomilling, needle scaling.

abrasive blasting shot blasting Impact scarifying milling scabbling needle scaling Figure 4 Expansive pressure Two forms of expansive pressure are used to modify concrete surfaces: steam and water.

Steam: Energy from a high-temperature heat source rap-idly heats the capillary and adsorbed water present in the cement paste to produce steam. This sudden increase in vapor pressure generates tensile stresses near the sur-face fracturing both matrix and aggregate, causing con-crete material to scale or pop off in thin, flake-like chips (figure 5). Because the water heats more rapidly than the surrounding concrete phases, concrete temperatures in the top 2 mm typically do not exceed 2500 C at rec-ommended travelrates. At this exposure level, substrate temperatures at a depth of 7 mm do not rise above 70' C. Best results are achieved when surfaces to be prepared are soaked with ponded water for several hours prior to flame scaling.

Although the mechanical properties of cement paste in compression are not significantly altered at tempera-tures below 300' C, the fracturing produced by this Figure 3 03732-4 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 7 of 43 CON1EtTh IU \\PA1R A0% 1* HRN AT -r 0 N-A Expansive pressure flame blasting Figure 5 method of cutting may introduce additional micro-crack-ing near the free surface of the substrate to cause some reduction in tensile strengths. The limited test data avail-able on the effects of this preparation method on the mechanical and durability properties of concrete are inconclusive. Further investigation into the condition of substrates prepared using this technique is needed.

Applicable methods: flame blasting (flame scaling)

Water: Working at higher pressures, 15,000 - 45,000 psi (100- 300 MPa), water jetting can produce a cutting effect similar to that of steam. An initial pass over hori-zontal concrete surfaces to be prepared using this method is sometimes taken with milling or scarifying equipment to remove 1/4 to 1/2 inch (6 - 13 mm) of the original sur-face. The purpose is to introduce the cracks and micro-cracks needed to create numerous avenues of entry be-neath the surface. The expansive pressure generated by water subsequently penetrating the fissures at high ve-locity will cause tensile failure along these planes of weak-ness (figure 6). Applicable methods: high and ultra high-pressure water jetting Bruising Several of the preparation methods described are likely to reduce the tensile strength of the prepared substrate.

Field studies have shown that bond strengths achieved on surfaces prepared using high-impact mechanical methods are frequently lower than those on surfaces pre-pared using non-impact methods. This reduction in bond strength is caused by fracturing of the cement paste and loosening of aggregate without fully separating from the surface. This creates a weakened or "bruised" surface layer of interconnecting micro-cracks typically extend-ing to a depth of 1/8 -

3/8 inch (3 - 10 mm). Under mi-croscopy, the cracks are frequently seen to initiate at the surface at approximately a 450 angle and propagate hori-zontally to produce a weakened plane (figure 3). It is generally accepted that the extent of the damage increases with the weight and power of the equipment used.How-ever, the use of sharp, fine toothed cutters contacting the surfaceat a shallow angle may reduce or prevent the development of bruising. The relative risk of introduc-ing bruising or micro-cracking into the substrate is indi-cated for each method (figure 7).

(

Risk of Introducing Micro-Cracking 0 very low (I moderate 0 high Abras High and ultra high-pres ive (sand) blasting C)

Steel shotblasting Q Scarifying O Needle scaling ssure water jetting Q Scabbling

• Milling/rotomilling

• Flame blasting

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Figure 7 high and ultra high-pressure water jetting Figure 6

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SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-5

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INTERNATIONAL SIc-iL CONCRETE REPA. R 1

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EC 75219 Page 8 of 43 A)

Specifying concrete surface profiles (CSP)

Several of the methods summarized are capable of pro-ducing a range of profiles on concrete surfaces. Com-munication of project requirements may be improved by using CSP profiles to define surface roughness.

ICRI has identified nine distinct profile configura-tions which may be produced by the methods summa-rized herein. As a set, these profiles replicate degrees of roughness considered to be suitable for the application of one or more of the sealer, coating, or polymer overlay systems, up to a thickness of 1/4 inch (see Appendix B).

Each profile carries a CSP number ranging from a base line of CSP 1 (nearly flat) through CSP 9 (very rough).

The profile capabilities for each preparation method are identified by CSP number in the "Profile" section of the method summaries. Molded replicas of these profiles are included with this guideline to provide clear visual stan-dards for purposes of specification, execution and veri-fication. These benchmark profiles may be referenced in specifications, material data sheets, application guide-lines, and contract documents to effectively communi-cate surface preparation requirements. When these pro-files are used in conjunction with specifications for thicker coating and overlay systems, it is probable that more than one profile will produce acceptable results.

When applicable, the range of suitable profiles should be specified.

The concrete surfaces shown below were produced using a variety of preparation methods. Although each numbered CSP plaque bears the characteristic pattern and texture of the specific preparation method used, each plaque is representative of the profile height ob-tainable with all methods identified with the same CSP number.

)

CSP I CSP 2 (acid etched)

(grinding)

CSP 3 (light shotblast)

Images generated using video density imaging techniques are courtesy of David Lange, Department of Civil Engineering, University of Illinois at Urbana-Champaign.

CSP 4 CSP 5 (light scarification)

(medium shotblast)

CSP 6 (medium scarification)

CSP 7 (heavy abrasive blast)

CSP 8 (scabbled)

CSP 9 (heavy scarification) 03732-6 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 9 of 43 INTERNATIONAL t

COPWCRETE REPAIR I N S T I T L T F

Method selector Coating to be applied Sealers 0 -3 mils (0 - 75 pm)

Thin-Film 4-10 mils (100- 250 pm)

High-Build 10-40 mils (250-o1000 ;1m)

Self-Leveling 50 mils - 1/8 Inch (1250 gmr-3 MmTI)

Polymer Overlay ý/s

-1/4 inch (3 -6 MITI)

Preparation methods

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Detergent scrubbing Low-pressure water cleaning Acid etching Grinding Abrasive (sand) blasting Steel shotblasting Scarifying Needle scaling High/ultra high-pressure water jetting Scabbling Flame blasting Milling/rotomilling SELECTING ANIJ SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-7

INTERNATIONAL wi(111 CONCRETE REPAIR glIN o3 T I T U r E EC 75219 Page 10 of 43 EC 75219 Page 10of43 Inoto: iennant uompany Detergent Scrubbing Chemical removal of oil, grease, and other deposits on concrete surfaces by scrubbing with a detergent solution.

Method summary This method can be used indoors or outdoors on hori-zontal concrete surfaces to remove dirt, oil, and grease.

Comer and edge cleaning can be detailed manually. The scrubbing process should produce clean surfaces, devoidt of dirt, oil, grease, and loose debris without altering sur-face texture.

Purpose. Detergent scrubbing is frequently used to pre-pare concrete for acid etching. It may also prepare con-crete surfaces for the application of sealers or surface hardeners, or for adhesive bonding.

Limitations. This method is limited to the removal of water-soluble or detergent-emulsifiable contaminants. (De-bris which is readily loosened may be removed by light mechanical action by the scrubbers).

Removal. Suitable for superficial removal of oil, grease, organic or inorganic residues, some acrylic, wax, or rub-ber membranes, rust, and other oxidation deposits from concrete surfaces. Absorbed fluids such as oils and grease may require several treatments to achieve acceptable re-sults. Bugholes and open pores at the surface may be scrubbed to a depth of 6-10 mils (150-250 gm).

Pattern. Detergent scrubbing will not produce any no-ticeable pattern effect on sound concrete surfaces.

Profile. ICRI CSP 1 A clean surface devoid of oil, grease, buildup, and loose debris. The scrubbing process should not alter surface texture.

Accessibility. With the variety of portable and maneu-verable equipment available, most surfaces are acces-sible. Access to corners, recesses, and between penetra-tions is restricted by the reach and arc of the brushes. These areas may be addressed manually.

Environmental factors. Moderate to heavy contamina-tion may produce significant amounts of sludge or other debris. Some debris may be considered hazardous or oth-erwise unqualified for discharge into sewer systems.

Debris produced by detergent scrubbing will contain par-ticles of material or contaminants being removed. Any special requirements for containment and disposal will depend on the specific materials or contaminant being removed. Materials likely to require special handling in-clude tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electrical equipment.

Suitable measures for the containment, collection, and proper disposal of debris and rinse water should be con-sidered. Though nontoxic, some citric acid-based clean-ing solutions have a pervasive odor.

Execution

, Apply chemical detergent solution.

• Scrub in chemical solution with stiff-bristled broom or scrubbing machine.

Collect and dispose of solution.

• Repeat process as needed to achieve acceptable results.

Equipment Manual method:

" mop

" stiff broom

" pressure washer

-squeegee

• wet/dry vacuum

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03732-8 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 11 of 43 1N4T V R1 NA T N'A L.

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Mechanical method:

" Automatic scrubbing machine (walk-behind or self-pro-pelled). Available in gas, electric, propane, or diesel-pow-ered models. Brush rotation speeds up to 300 rpm.

" Brushes (disc or cylindrical pad). Nylon bristle brushes are relatively soft. Polyethylene bristles are stiffer, more aggressive. Polyethylene/abrasive composite bristles will provide the most aggressive mechanical cleaning.

Sizes range from 18 -. 60 inch (0.5 - 1.5 m) brush path.

" Solution tanks range from 3 - 365 gallons (11 - 1,380 L) with recovery tanks to hold scrubbing residue.

Materials

" Industrial detergent rated to remove heavy oil and grease

" Water source Labor. Low skill for manual scrubbing method. Medium skill to operate automatic scrubber and mix chemical solutions.

Down time. (The time considerations which follow are applicable to automatic scrubber machines). Mixing chemicals, filling tanks, and removing soilage from re-covery tanks will involve some down time. For example, a 100 gallon (380 L) tank may take 20 - 30 minutes to fill. Changing brushes is quick and infrequent. Replace-ment frequency for pickup squeegees will depend.on wear factors.

Cleanup. Scrubbing manually with brooms or mechani-cally with electric single disc machines will generate a liquid residue which must be removed by squeegee and vacuum to obtain a clean surface. Automatic scrubbers have an internal squeegee/vacuum system to remove the liquid residue immediately behind the scrubbing brushes.

Production rates. The following rates are approximate.

Actual rates will vary considerably with the severity of soil, size of machine, and effectiveness of chemical so-lution being used.

" Manual with wet/dry vacuum recovery: 500 ft2 (50 m2) per hour.

" Manual with electric disc machine with wet/dry vacuum recovery: 1,000 ft2/hr (100 m2/hr)

" Small walk behind scrubber: 5,000 ft2/hr (500 m/hr)

" Medium or large riding scrubber: 50,000 ft2/hr (5,000 m2/hr)

Standards i specifications As required by the specifications of the manufacturer or customer.

Surfaces scrubbed in preparation for etching must be clean enough to allow chemical etching solutions to bite into cement paste. Inspection may consist of one or a combination of the following methods:

" Visual inspection should show no dirt, oil, grease, or debris on the surface.

" The prepared surface should be free of bond-inhibit-ing barriers and demonstrate sufficient strength for the proposed application.

" Gloss meter, slip tester/traction recorder.

" A solution hand scrubbed across area to be tested. Re-covered solution should be clear.

ACI 515. IR describes methods and criteria for judging surface cleanliness and strength (see ref. page 41).

Safety

- Eye protection: Required.

- Personal protective equipment: Latex gloves, boot protection.

" Respiratory protection: Not required.

" Hearing protection: Recommended if automatic scrub-bers are used.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-9

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EC 75219 Page 12 of 43

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Low-Pressure Water Cleaning Water is sprayed at pressures less than 5,000 psi to remove dirt and loose, friable material.

This method does not remove any significant amount of concrete.

Method summary This method may be used outdoors to remove dust, fri-able materials, debris, or water-soluble contaminants from concrete surfaces and surface cavities. It may be used in interior spaces where mist, noise, and severe pud-dling can be tolerated. The method is suitable for hori-zontal, vertical, and overhead applications. This method does not produce any significant texture, profile, or pat-tern. For surface preparation applications, low pressure water cleaning should supplement other methods.

Purpose. Low-pressure water cleaning is used to rinse away dirt, dust, loose scale or debris generated by more aggres-sive surface preparation methods.

Limitations. This method is not suitable for the removal of sealers, coatings, curing membranes, or any signifi-cant volume of concrete.

Removal. Low-pressure water cleaning will not produce any measurable removal of sound concrete.

Pattern. Low-pressure water cleaning will not introduce any noticeable pattern effect on sound concrete surfaces.

Profile. ICRI CSP I Accessibility. With the wide variety of portable and ma-neuverable equipment available, most surfaces are eas-ily accessible. Tight spaces can be accessed with a hose and hand-held lance. Presence of goods or equipment that cannot be adequately protected from mist or spray may restrict use of this method.

Environmental factors. This process produces loud noise similar to sandblasting. Mist and a large volume of wa-ter will be introduced into the work area.

Debris produced by low-pressure water cleaning will contain particles of material or contaminants being re-moved. Any special requirements for containment and disposal will depend on the specific materials or con-taminant being removed. Materials likely to require spe-cial handling include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electri-cal equipment.

Environmental regulations may require containment and regulated disposal of the liquid waste generated.

Execution

" A water jet is methodically moved back and forth over the surface until the desired results are achieved. If au-tomated equipment is used, the operator typically makes parallel passes. If hand-held lances are used, the pro-cess will be slower, but similar,

" Standing water may need to be pumped, vacuumed, or squeegeed off the surface.

" Solid debris and water residue are disposed of as re-quired by local regulations or project restrictions.

Equipment

" Booster pump (to increase pressure)

" Pressure rated hoses

• Water jet: wheeled equipment for horizontal surfaces; hand-held lance for vertical and overhead applications, corners, or other difficult-to-reach locations

• Suitable nozzle tip

" Runoff protection to catch debris flowing off site or toward drains

-y 03732-10 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 13 of 43 I NT R N A'T ON A L RvAK411p CONCREiTE REPAIR 14,00I*

Materials. Water source may be provided by tanker, hy-drant connection, industrial spigot, or pump.

Labor. Generally requires a two or three-person crew.

Work may be performed with unskilled labor. Skilled supervision may be needed if complex equipment is used.

Down time. Setup time is typically two to four hours to protect surfaces and install runoff protection to catch loosened materials. Production may shut down periodi-cally if water must be transported to the work area.

Cleanup. Several hundred gallons of water per hour may need to be drained away. The volume of debris trapped by collectors is usually small.

Production rates. The rates below are approximate. Ac-tual rates will vary with the efficiency of equipment employed and preparation objectives.

• 1,000 - 2,000 ftfhr (100 -200 m2/hr) for flat surface.

• 250- 1,000 ft/hr (25 - 100 m2/hr) for hand-held equip-ment on vertical surfaces.

Standards Et specifications Visual inspection should find no obvious dirt, laitance, or debris on the surface. The prepared surface should be free of bond-inhibiting barriers and demonstrate suffi-cient strength for the proposed application. Beads of wa-ter indicate a surface contaminant that may need to be removed by other means. ACI 515.1R describes meth-ods and criteria for judging surface cleanliness and strength (see ref. page 41).

Safety

" Eye protection: Anti-fog goggles or face shield.

• Personal protective equipment: Rugged rubber or plas-tic gloves, steel-toed boots, and waterproof outer-layers.

" Respiratory protection: Not required.

" Hearing protection: Recommended.

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SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-11

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-FItNAr I ONA L I dcili CONCRETE REPAIR IIN S T I T U T E EC 75219 Page 14 of 43 innoo: iennanm mompany Acid Etching Chemical removal of cement paste to clean and condition concrete surfaces prior to application of thin-film sealers or coatings.

Method summary Acid etch is a mixture of water-soluble solvents, sur-face-active agents, and suitable acids designed to remove (etch) cement paste from the surface and pores of con-crete. It also aids in dislodging slight traces of oils, grease, or fats remaining after detergent scrubbing. Etch-ing produces a clean, lightly-profiled concrete surface to promote penetration and adhesion of sealers and coat-ings. The process will almost always be used to prepare concrete surfaces for the application of thin-film coat-ings. The process can be used inside or outside on most concrete, quarry tile, or stone surfaces.

Purpose. Etching is used to remove weak cement paste and to slightly profile the surface by exposing fine aggregate.

This process is used to prepare concrete surfaces for the application of concrete sealers or thin-film epoxy, urethane, acrylic, and alkyd coatings.

Limitations

" Not suitable preparation for systems greater than 10 mils.

" Thorough removal of etching debris requires the use of vacuuming equipment.

" Solution is highly corrosive. Electronic equipment, machines and other metal components should be pro-tected or removed.

" Thorough removal of etching debris requires large quantities of rinse water, mechanical scrubbing, and vacuum removal. (Incomplete removal will leave bond-inhibiting contaminants on the surface.)

" Hydrochloric acid may not be used on metallic hard-ened surfaces.

" Oils, grease, and other surface deposits must be re-moved prior to etching

" Not recommended for use on green concretes. Mini-mum age is six weeks.

" The etching process will saturate the substrate. When used in preparation for moisture-sensitive coatings, time restrictions may not allow for sufficient drying.

" Environmental considerations may require full contain-ment and recovery of spent acid and rinse water.

Removal. The acid in the etching solution attacks the Ca(OH) 2 and C-S-H in the cement paste causing rapid deterioration at the surface. The concentration and vol-ume of solution applied are controlled to limit the depth of chemical attack. Typical depth of removal is 4 to 10 mils (100-250 gim).

Pattern. Etching should not introduce any noticeable pat-tern effect on sound concrete surfaces.

Profile. ICRI CSP 1 - 3 Surface should feel like fine sandpaper with no residue or grit. Surface should have a dull, even appearance. If surface is stillsmooth or glossy, repeat procedure.

Accessibility. The equipment used for this method is por-table and maneuverable. Access may be restricted by the presence of non-portable machinery or equipment subject to damage from corrosive mist or splash.

Environmental factors. Applied as an acid wash, the mix-ture may corrode metals on contact. Debris produced by acid etching will contain particles of material or con-taminants being removed. Any special requirements for containment and disposal will depend on the specific materials or contaminant being removed. Materials likely to require special handling include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vi-cinity of electrical equipment. Spent acid and rinse wa-

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03732-12 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 15 of 43 401kINTL NNA TION A l Cit OM, 0MCETE REPAIR tN F; T IT U T F_

ter should be disposed of as required by local regula-tions or project restrictions. Careful control of the etch-ing process can produce a residue solution having a slightly alkaline pH of 8 or 9.

Execution

" Dilute acid mixture according to floor type and strength of concentrate. For standard concrete, use manufacturer's ratio. The usual concentration is approximately 10%.

Dense or chemically-hardened floors may require higher concentrations and/or multiple passes.

• Thoroughly wet concrete surfaces. Any standing wa-ter must be removed prior to application of acid.

" Apply mixed solution uniformly at an approximate rate of 100 square feet (9 m2) per gallon.

" Agitate acid solution with stiff bristle broom or power brush for five to ten minutes. Do not allow surface to dry. Vacuum residue.

" Thoroughly scrub with an alkaline detergent and vacuum residue. Repeat as necessary to completely remove etching debris.

• Rinse with clean water, scrub and vacuum dry.

• Allow floor to dry for a minimum of 12 - 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />.

Equipment

" Container to mix etching solution

• Applicator: Low pressure sprayer, plastic sprinkling can, or mop

• Floor scrubber or disc machine equipped with an abra-sive bristle brush

" Power washer or hose to apply rinse water

• Vacuum system or scrubber for recovery The use of automatic scrubbing equipment to apply acid etching solution is not generally recommended. How-ever, this equipment is often used to recover etching so-lution after it has been diluted with rinse water Consult equipment manufacturer to determine suitability.

Materials

" Acid etch solution. Typical solutions include muriatic (hydrochloric), sulfamic, phosphoric, and citric acids.

• Alkaline detergent for cleanup scrub

" Water source

• Plastic sheeting for machine protection Labor. Medium to above medium skill level required to safely handle and mix hazardous materials and to oper-ate equipment.

Down time. Minimal. Chemical mixing requires only a short period of time. Filling and emptying scrubber and wet-vac tanks should take ten to twenty minutes. Addi-tional time required to remove portable machinery from etch area and to place plastic sheeting on non-portable machinery for protection.

Cleanup. While the surface is still wet, squeegee and vacuum acid solution and slurry debris. Immediately flood surface with alkaline detergent solution, scrub and vacuum. Some acid etching solutions produce a white residue which helps identify locations requiring addi-tional scrubbing, rinsing, and removal. Flood etched sur-face with clear rinse water, scrub, and vacuum dry.

Production rates. The rates shown below are approxi-mate. Actual rates will vary with the method used, den-sity of surface, dilution ratio, and size of machines.

" Manual with wet/dry vacuum recovery:

1,600 ft2/hr (150 m2 hr).

" Medium scrubber: 8,000 ft/hr (740 m2/hr).

Standards E specifications As required by the specifications of the manufacturer or customer.

Visual inspection should show a fine-grained surface pro-file with no white residue, dirt or debris remaining on sur-face. Dry surface check using a moisture meter. The pre-pared surface should be free of bond-inhibiting barriers and demonstrate sufficient strength for the proposed appli-cation. ACI 515.1R describes methods and criteria forjudg-ing surface cleanliness and strength (see ref. page 41).

Safety

" Eye protection: Splash shield recommended.

" Personal protective equipment: Gloves, aprons, and boot protection required. Recommended materials for these items are neoprene or rubber.

• Respiratory protection: Use of respirators equipped with acid-gases canister is recommended for acid etch-ing in poorly ventilated or confined space.

" Hearing protection: Required if automatic scrubbers are used for cleanup.

" Alkaline detergent can be used to neutralize concen-trated acid spills.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-13

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Grinding The rotation of one or more abrading stones or discs applied under pressure at right angles to the concrete surface.

Method summary This method may be used on horizontal, vertical and overhead surfaces to remove deposits or coatings, and to reduce or smooth surface profile. The grinding stone or disc is applied under pressure and moved across the surface until the desired effect is achieved. Grinding may be used on almost any substrate and is suitable for both interior or exterior applications. Efficiency consider-ations may limit coating iemoval applications to film thicknesses less than 6 mils (150 gim).

Purpose. Grinding is used on concrete surfaces to re-duce or smooth slight surface irregularities and to re-move mineral deposits and thin coatings.

Limitations. Grinding is not recommended for the fol-lowing applications:

" Preparation of previously sealed or coated surfaces for recoating-unless followed by acid etching or shotblast.

" Surface profile is required.

" Removal of chlorinated rubber, acrylic, or other soft coatings or finishes.

" Removal of tile or carpet adhesives.

" Occupied work space (unless rigorous dust control methods are used).

S.Surfaces of unknown composition.

Removal. Removal is practically restricted to surface pro-trusions and coatings less than 6 mils (150 jim) thick. May be used to remove noncombustible or non-heat degen-erating coatings. Method will successfully remove rigid epoxy, polyurethane, and methacrylate coatings. Grind-ing may also be used to remove efflorescence, rust, and other oxidized deposits.

Pattern. Small hand-held grinders are likely to produce gouging and a circular, grooved pattern. Large walk-behind units fitted with aggressive media should elimi-nate gouging, but are likely to impart a circular pattern.

Larger units using fine stones should not produce any detectable pattern.

Profile. ICRI CSP 1-3 Grinding produces a smooth surface. Other methods may be used in conjunction with grinding to produce required profile.

Accessibility. Most surfaces, including edges, are acces-sible. Portable equipment ranges from small hand-held grinders to walk-behind units with multiple discs. Ac-cess to corners and tight configurations is restricted by the arc ofthe grinding disc.

Environmental Factors. Dry grinding will produce a fine airborne dust which may be minimized with dust con-'

trol attachments. Debris generated by this method will contain fine particles of any material or contaminant being removed. Materials likely to require special pro-tective measures and handling include tile mastics, which may contain asbestos; lead-based paints; and PCB's which may have been absorbed by concrete in the vicin-ity of electrical equipment. Wet grinding, which may be selected to eliminate airborne dust, will produce a slurry residue. Slurry constituents from some materials may be considered toxic. Plans to collect and properly dis-pose of slurry and rinse water must be considered. Grind-ing soft, easily charred materials will generate smoke which may be considered hazardous.

Preparation should include plans to adequately protect occupants and workers. Noise and vibration levels are considered to be low.

03732-14 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 17 of43 IN S

1-U T 1-1 Execution Equipment. Appropriate selection of a grinder depends on the location and size of the area, specific removal re-quirements, and accessibility. They are available in elec-tric, pneumatic, or gas-driven models. Sizes range from hand-held grinders to walk-behind machines. Rotation speeds vary from 1,000 to 9,000 rpm.

Materials. The grinding medium (stone or disc) is the consumed material, and will vary with job specific ap-plication requirements:

" Size: diameter ranges from 4-18 inches (100-450 mm).

" Composition: varies from very fine polishing media to aggressive cutting media with wet or dry diamonds.

" Shape: flat, cone-shaped, or cup disc.

Labor. Low to medium skill required.

Down time. Minimal. Setup requires very little time un-less dust protection includes draping and taping. Chang-ing stones or discs is quick. Frequency of replacement will depend on the composition of the stone or disc, sub-strate, and material being removed.

Cleanup. Grinding will leave a fine powdered residue of the removed material. The residue generated can be swept, rinsed with water, or vacuumed.

Production rates. Productivity will vary depending on grinding media selected and the type of material being removed. Estimated rates are:

" Hand-held units: 20 ft2/hr (2 m2/hr)

" Walk-behind units: 800 ft2/hr (75 m2/hr)

Standards h specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile objectives. The pre-pared surface should be free of bond-inhibiting barriers and demonstrate sufficient strength for the proposed application. ACI 515. 1R describes methods and criteria for judging surface cleanliness and strength (see ref.

page 41).

Safety

" Eye protection: Required.

" Personal protective equipment: Heavy gloves, steel-toed boots. Skin should be protected by clothing and barrier creams. Dust may produce alkali burns or al-lergic skin reaction.

• Respiratory protection: Required. Process will gener-ate airborne dust. Mask should be approved for silica and other airborne dusts, and fit tightly to contours of face. If material being ground contains toxic substances, additional protection may be required.

• Hearing protection: Recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-15

ction ZOO SINTERNATIONAL 00tB K

OPCRETE REPAIR IN S T 1T U 7r E EC 75219 Page 18 of 43 Abrasive (Sand)

Blasting This method uses compressed air intermixed with an abrasive medium to clean concrete or steel surfaces. The air stream is channeled through a nozzle directly at the surface.

Method summary Abrasive blasting is used to clean and profile concrete surfaces in preparation for the application of sealers, coat-ings, and polymer overlays. The process can provide a light cleaning profile, often referred to as a "brush blast,"

or it can be used to achieve a much heavier surface lin-eation for deep cleaning and profiling. It may also be used to remove surface contaminants and thin, brittle coatings, or adhesive films. Water may be introduced into the blast process to reduce airborne dust. Vacuum recovery systems may also be used with abrasive blast units to reduce dust and cleanup. This method may be used on horizontal, vertical, and overhead surfaces, and is suitable for both interior and exterior applications.

Purpose. Abrasive blasting is a highly flexible process capable of producing a range of profiles suitable for the application of the following systems:

- sealers: 0 - 4 mils (0 - 100 tm)

" thin-film coatings: 4 - 10 mils (100 - 250 gim)

" high-build coatings: 10 - 30 mils (250 - 750 jim)

" broadcast systems: 30 mils - 'A inch (750 im - 6 mm)

" monolithic toppings: 1/s - 'A inch (3 - 6 mm)

Limitations. Abrasive blasting typically generates a large volume of airborne dust. Increased profiles may become visible through concrete sealers and thin or clear coat-ings, producing an unsightly finish.

Abrasive blast is not recommended for the following applications:

" Removal of resilient coatings, uncured coatings or ad-hesives, and tar-based materials.

" It should not be used when occupied space, goods, or equipment cannot be adequately protected from dust infiltration.

" High volume concrete removal.

Removal. Removal is accomplished by the eroding ef-fect of the blast media impacting the surface at high ve-locity. Depth of removal may range from a minimum of 1 - 2 mils (25 - 50 gtm) to a practical maximum of 30 mils (750 jim).

Pattern. Abrasive blasting should not introduce any no-ticeable pattern effect.

Profile. ICRI CSP 2 - 4 Profile achieved is dependent upon duration of expo-sure to blast stream and size and cutting efficiency of blast media used.

Accessibility. The small size and portability of hose and blast nozzle provide virtually unrestricted access to all surfaces including edges, corners, and recessed spaces.

Environmental Factors. Abrasive blasting will produce airborne dust containing silica, concrete constituents and particles of any material being removed. Special provi-sions are often needed to protect people, property, and the environment. Blast curtains and containment areas may be used to isolate the blast process. Blast media substitutes such as sodium bicarbonate are sometimes used to reduce the dust hazard or volume of debris.

Any special requirements for containment and disposal will depend on the specific contaminants or materials being removed. Materials likely to require special han-

/

03732-16 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 19 of 43 I~NTER~NATIONr'AL K~I1IJP CONCRETE REPAIR t

1 1

dling include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electrical equipment. Noise levels are likely to exceed 85 dB.

Execution The blast media stream is directed at the surface using a controlled sweeping motion. The duration of exposure to the blast stream depends on the strength of substrate and the degree of cleaning and profiling required.

Equipment

" Air compressor of sufficient capacity to drive the equip-ment and blast media selected

• Blast media hopper (meters the media into the air stream passing through the hose and nozzle)

• Moisture and oil separators to insure clean, dry air supply

" Blast nozzle and hose Materials. The blast medium, e.g. silica sand, slag (black beauty), etc. is the consumed material.

Labor. Medium to above-medium skill level required.

Special training in safe operation and related environ-mental issues is recommended for crew members. Two workers per blast unit is standard-one to operate the blast nozzle, the other to support the blast media.hopper and compressor and to manage the hoses.

Down time. Hours needed for setup and removal of work area protection may be significant. Time required for mobilization, setup, and maintenance of blast equipment and compressor is minimal.

Cleanup. Dust, fine particles of concrete or other pul-verized materials, and a relatively large volume of ex-pended blast media are generated by the abrasive blast process. Water soluble blast media, which can be flushed into conventional drainage systems, may substantially reduce the volume of debris to be collected and removed.

Production rates. Productivity is highly variable and is dependent upon the strength of the concrete, any surfac-ing materials or contaminants, accessibility, capacity of blast media hopper and compressor, and type of blast media used.

Production rate estimates range from 1,000 - 6,000 square feet (100 - 600 m2) per eight hour shift per unit.

Standards & Specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, bond-inhibiting bar-riers, and demonstrate sufficient strength for the pro-posed application. ACI 515. 1R describes methods and criteria for judging surface cleanliness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of specified contaminants.

Safety

" Eye protection: Required.

• Personal protective equipment: Helmet, hood, and heavy gloves, boots and clothing are recommended for blast nozzle operator. Skin should be protected by cloth-ing and barrier creams. Dust may produce alkali burns or allergic skin response.

• Respiratory protection: Required. Supplied air system is routinely used for blast nozzle operator.

" Hearing protection: Required.

• Safety devices: Blast nozzle must be equipped with an automatic shut-off device.

M SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-17

_ection ZOO INTE R N AT IONA.

CONCRETE REPAIR EC 75219 Page 20 of 43 h

1.

Steel Shotblasting Steel shot is centrifugally propelled at high velocity onto the surface. This process is confined in an enclosed blast chamber which recovers and separates dust and reusable shot.

Method summary Shotblasting is principally used to roughen horizontal surfaces in preparation for the application of sealers, coat-ings, or polymer overlays. This method is also used to remove some existing coatings, adhesives, and surface contaminants. Hand-held machines are available for use on vertical surfaces. Shotblasting is suitable for use in both interior and exterior applications.

Purpose. Cleaning and profiling concrete surfaces by removing dirt, laitance, curing compounds, sealers, or other superficial contaminants in preparation for the ap-plication of protective materials.

Shotblasting is suitable for the removal of polyurethane coatings up to 10 mils (250 jim) thick, tile mastics, and brittle coatings such as epoxy or methyl methacrylate systems up to /8 inch (3 mm) thick. Removal of thicker materials may require multiple passes.

Limitations. This method is generally not suitable for removing uncured resin systems, resilient coatings, ad-hesives, and tar-based materials. The pattern and profile of shotblasted surfaces may be visible through concrete sealers and thin or clear coatings.

Removal. Removal is accomplished by the pulverizing effect of steel shot impacting the surface at high veloc-ity. Depth of removal is controlled by shot size, ma-chine setup, and rate of travel. Generally, the maxi-mum recommended depth of removal for a single pass is 114 inch (6 mm).

Pattern. The "double exposure" that occurs at the point of overlap between successive passes produces a paral-lel striping effect at intervals determined by the width of cut. Skilled operation of equipment can minimize striping effect.

Profile. ICRI CSP 2 - 8 As the depth of cut increases, the profile will be increas-ingly dominated by the size and shape of the coarse aggregate.

Accessibility. Shotblasting equipment is available in a range of sizes to provide ready access to most surfaces.

Edges and corners may be detailed to within 11/44 inch (6 mm) of the vertical surfaces with specialty edging machines or hand-held units. Access to tight configura-tions, such as around and in between pipes, is restricted by the width of the machine used.

Environmental Factors. Shotblast systems produce very little airborne dust or contamination. Most models can be fitted with a filter to further lower the level of air-borne dust produced.

Debris produced by shotblasting will contain particles of material or contaminants being removed. Any spe-cial requirements for containment and disposal will de-pend on the specific materials or contaminant being re-moved. Materials likely to require special handling in-clude tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electrical equipment.

Special ventilation provisions may be required when operating gasoline, diesel, or propane-powered units indoors.

With the exception of some large machines, noise levels will usually be below 85 dB. Vibration is not consid-ered to be a factor.

03-732-18 0373-18 SELECTING AND SPECIFYING CONCRET SURFACE PREPARATION FOR

SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 EC 7219Page 21 of 43 IN T LF. R N AT 10C N AL._

I T Li T F.

Execution The machine is steered in a straight line across the sur-face. At end of each pass, the machine is turned around and steered parallel to the previous path with minimum overlap. Some overlap is required to prevent the devel-opment of unprepared strips between passes.

Equipment

" Shotblasting machine: available in gasoline, diesel, propane, or electricaily-powered units

" Power source: requirements for electric powered units will vary from 110/120 V @ 26 A to 460 V @ 60 A

" Brooms and shovels

" Spare parts for blaster maintenance

" Magnets or magnetic broom to retrieve fugitive steel shot Materials. Steel shot is the consumed material. Con-sumption ranges from 10 to 20 lbs/hr. Commonly used sizes of steel shot are shown below:

T-p-i

-PrIle Down time. Surfaces must be dry and broom cleaned prior to shotblasting. A test area is required to insure that media size and machine adjustment will achieve desired performance. Replacement of worn blasting wheels and liners is required every 20 to 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> and will take 20 to 45 minutes. Equipment is shut down ev-ery 30 to 60 minutes to remove debris from collection system.

Cleanup. Steel media may remain on the surface, in edges or corners, or trapped in cracks. It may be recovered by using magnets, magnetic broom, air blast, vacuum, or stiff bristle broom.

Production rates. The following rates are approximate and assume sound, 5,000 psi (35 MPa) concrete. Actual production rates will vary considerably and will depend on the strength of the concrete, the type of material be-ing removed, preparation objectives, operator skill, and efficiency of equipment employed.

Small units: 150 - 250 ft2/hr (14 - 23 m2/hr)

Medium units: 350 - 1,500 ft2/hr (33 - 140 m2/hr)

Large units: 2,000 - 4,500+ ft2/hr (190 - 420+ m2/hr)

Standards h specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, bond-inhibiting bar-riers, and demonstrate sufficient strength for the pro-posed application. ACI 515.IR describes methods and criteria for judging surface cleanliness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of specified contaminants.

Safety Eye protection: Required.

Personal protective equipment: Skin protection may be required during removal of hazardous materials and han-dling of debris.

Respiratory protection: May be required during removal of hazardous materials and handling of debris.

Hearing protection: Recommended.

S-1 701 0.017 in. (0.43 mm)

CSP 32 S-230 0.023 in. (0.58 mrm)

CSP 3 S-280 0.028 in. (0.71 Trim)

CSP 3 S-330 0.033 in. (0.84 mm)

CSP 5 S-390 0.039 in. (1.0 mm)

CSP 5 S-460 0.046 in. (1.17 mm)

CSP 7 S-5501 0.055 in. (1.40 mm)

CSP 7 1

Use of this size is not recommended by all manufacturers.

2 Association of profile with shot size is not precise as profile obtained is also influenced by machine set up and rate of travel, Labor. Experienced or well-trained personnel to operate equipment is recommended. One worker with interme-diate mechanical skills can operate and maintain most shotblast systems. Large, electrically-powered machines require connection to a three-phase, high-voltage power source which may require a licensed electrician, SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-19

0 ion ZOO

~l C0NTICRETE REPAIR QI N S T I T UJ T E EC 75219 Page 22 of 43 Photo: Restruction Corporation Scarifying The rotary action of the cutters (toothed washers) impacts the surface at a right angle to fracture or pulverize the concrete. The cutters are assembled on tempered steel rods mounted at the perimeter of a drum which rotates at high speeds.

Method summary Scarification is used primarily on horizontal surfaces for the removal of concrete or brittle coatings up to 1/8 inch (3 mm) thick. It may also be used to profile concrete surfaces. Hand-held units are available for vertical, and overhead applications. Scarifying may be used on al-most any substrate and is suitable for both interior or exterior applications. This method is also known as con-crete planing.

Purpose

" The removal of brittle coatings such as epoxy, poly-urethane, or methyl methacrylate systems up to 1/8 inch (3 mm) in preparation for the application of replace-ment coatings.

" Removal of deteriorated or contaminated concrete to depths ranging from 1/8 to 3/4 inch (3 - 19 mm) depend-ing on the strength of the substrate, cutter configura-tion, and size and power of the machine.

" Removal of high spots in order to level slabs.

" Profiling of concrete surfaces in preparation for the application of high-build coatings greater than 15 mils (375 jim), self-leveling systems, broadcast, thin over-lays or placement of other repair materials.

" Removal of adhesives may be accomplished by the ad-justment of spacers and the selection of appropriate cutters.

Limitations. Scarification is not recommended for sur-face preparation for sealers or coatings less than 15 mils (375 gm) or the removal of heavy elastomeric membranes.

This method may cause micro-cracking in substrate. (It has been demonstrated that micro-cracking will reduce the strength of the bond between the substrate and ma-terials placed over it.) The deleterious effects of micro-cracking may be reduced or eliminated by following initial removal with steel shotblasting, abrasive blast-ing, or high and ultra high-pressure water jetting. The use of sharp, fine-toothed cutters may prevent the de-velopment of micro-cracking.

Removal. Removal depth may economically range from light surface profiling to 1/4 inch (6 mm) for smaller equipment, and V2 -

3/4 inch (13 - 19 mm) for larger equipment. Removal depth greater than VI8 inch (3 mm) is accomplished in multiple passes.

Pattern. Scarifying will produce a parallel, striated pat-tern. The deepest striations will be produced at surface high points.

Profile. ICRI CSP 4 - 9 Accessibility. With portable equipment ranging in size from small hand-held scarifiers to large self-propelled units most surfaces are accessible to. within 1/4 inch (6 mm) of the edge. Access to corners and tight configu-rations such as around and in between pipes is restricted by the dimensions of the drum housing. The smaller walk-behind machines are able to pass through.standard door openings.

Environmental factors. Scarifying will produce airborne dust containing concrete constituents and particles of the material being removed. Any special requirements for containment and disposal of dust and debris will depend 03732-20 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 23 of 43 1h 11-1 EC 1-C AT IL ON A L 10CONCRETET REPAIR IN S, T r I T

F on the specific contaminants being removed. Materials likely to require special handling include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have-been absorbed by concrete in the vicin-ity of electrical' equipment.

Noise levels are likely to exceed 85 dB. Vibration levels are moderate. Special ventilation arrangements will be required when operating gasoline or diesel-powered units indoors.

Execution With the exception of hand-held units, most scarifiers are operated by pushing the machine forward over the surface, advancing at a slow walk. The depth and rate of cutting are adjusted by raising or lowering the drum to increase or decrease the impact of the cutters. Several passes may be required to achieve the desired profile.

Debris must be removed after each pass.

Equipment

" Scarifier: available in electric, pneumatic, or gasoline powered models in sizes ranging from hand-held to self-propelled ride-on units. Path widths range from 4 - 36 inches (100 - 900.mm)

" Replacement drums: plan on four drums per machine for each eight hours of continuous operation

" Air compressor or other air supply (pneumatic models only)

" Industrial vacuum cleaner to be used with vacuum adapter attachments to limit airborne dust Materials. The cutters are the consumed material. Rate of consumption depends on the following:

" Cutter configuration

" Cutter composition (hardened steel, tungsten carbide)

• Substrate hardness

" Composition of materials to be removed Labor. Low to medium skill required.

Down time. Minimal. Setup requires very little time un-less dust protection includes draping and taping.

Drum changes will take approximately five minutes. (See "materials" and "equipment" above to assist in estimat-ing frequency of drum change). Rebuilding drums is usu-ally an off-site activity..

Cleanup. Scarifying will generate dust and larger debris.

While most scarifiers are not equipped to pick up de-bris, many units have adapters which may be used with industrial vacuum cleaners to contain dust. Sweeping and removal of the rough debris will be required.

Production rates. The rates shown below are estimates.

Productivity will vary considerably depending on equip-ment size, depth of removal, and the type of material being removed.

" Hand held units: 20 ft2/hr (2 m2/hr)

• Walk-behind units: 800 ft2/hr (75 mr/hr)

Standards h specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, bond-inhibiting bar-riers, and demonstrate sufficient strength for the pro-posed application. ACI 515.1R describes methods and criteria for judging surface cleanliness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of specified contaminants.

Safety

" Eye protection: Required.

" Personal protective equipment: Skin should be pro-tected by clothing and barrier creams. Dust may pro-duce alkali burns or allergic skin reaction.

• Respiratory protection: Mask should be approved for silica and other airborne dusts, and fit tightly to contours of face. If materials being removed contain toxic sub-stances, additional protection may be required.

" Hearing protection: Recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-21

Section ZOO NI\\

1N AI"'NA IONA L CONCRETE REPAIR I N '

T I T U T I_

EC 75219 Page 24 of 43 r(IVtu; ýq qjiunII[I U -U P11IUI{Il UV,, JIM1G Needle Scaling Impacting the surface with pointed tips of a bundle of steel rods contained by a steel tube and pulsed by compressed air Method summary This method can be used on concrete surfaces indoors, outdoors, or underwater, to remove efflorescence, brittle encrustations, and rigid coating systems. It is frequently used for work on edges and other tight spaces which cannot be accessed by larger, more automated equip-ment. It may be used underwater to remove barnacles and other marine shell fish attached to submerged sur-faces. It is suitable for use on horizontal, vertical, and overhead surfaces.

Purpose. Needle scaling is used to remove coatings or brittle encrustations in preparation for the application of protective coatings or other repair work. It is an ex-cellent method for detailing corners, edges, and most recessed areas. It is suitable for preparing concrete sur-faces for high-build coatings, self-leveling and broad-cast applications, and thin overlays.

Limitations. Needle scaling is not recommended for the following applications:

" Preparation for coatings less than 15 mils (375 pin)

" Removal of thick, resilient coatings

" Preparation of large surface areas

" Removal of sound concrete Removal. Removal is accomplished by the superficial fracture and pulverization of concrete surfaces to which the unwanted material is adhered. Depth of concrete removal will typically be in the range of'/ 16 to 1/8 inch (1.5 - 3 mm) and is dependent on aggregate size and composition.

Needle scaling is generally suitable for the following removal applications:

• Rigid coatings to 15 mils (375 gm)

" Soft or flexible coatings to 30 mils (750 gm)

" Brittle deposits to 1/4 inch (6 nmm)

Pattern. Needle scaling will produce random, evenly dis-tributed impact craters around larger aggregate, impart-ing a heavy "orange peel" texture to the surface.

Profile. ICRI CSP 5 - 8 Accessibility. Hand-held needle scalers are available in sev-eral sizes providing virtually unrestricted accessibility.

Environmental factors. Debris produced by needle scal-ing will contain particles of any material or contami-nants being removed. Any special requirements for con-tainment and disposal will depend on the specific con-taminants being removed. Materials likely to require special handling include tile mastics, which may con-tain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of elec-trical equipment. Noise and vibration levels are low to medium.

Execution Rod (needle) points are held against the surface with light to medium pressure. The pneumatically driven rods are activated by a trigger located in the unit's handle.

Equipment

" Needle gun: several sizes of pneumatic, hand-held units are available which vary in weight from 2/2 - 15 lb.

(I - 7 kg). Size of rod bundle will vary from 12 to more than 30 rods.

" Replacement rod bundles: plan for six bundles per gun for each eight hours of continuous operation.

" Air hose

,'./

03732-22 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 25 of 43 R1411 ONC85UTE 5ni1-PAIn

_f I iI i F.

• Air compressor or other air supply producing 3 - 15 cfm @ 80 - 120 psi.

Materials. The hardened steel rods are the consumed material.

Labor. Low skill required.

Down time. Approximately five minutes per hour to change needle bundles. Rebuilding needle bundles is usu-ally an off-site activity.

Cleanup. Needle scaling will generate dust, small granu-lar particles or flakes. The tools are not equipped to col-lect debris, which may be vacuumed or swept up for proper disposal.

Production rates. Productivity will range from 10 - 50 ft2/hr (1 - 5 m2/hr). Rate is dependent on size of needle gun, number of needles per bundle, strength of substrate, and hardness of material being removed.

Standards Et specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, or bond-inhibiting barriers, and demonstrate sufficient strength for the pro-posed application. ACI 515.1R describes methods and criteria forjudging surface cleanliness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of specified contaminants.

Safety

" Eye protection: Required.

• Personal protective equipment: Skin should be pro7 tected by clothing and barrier creams. Dust may pro-duce alkali bums or allergic skin response.

" Respiratory protection: Process will generate airborne dust. Mask should be approved for silica and other air-borne dusts, and fit tightly to contours of face. If mate-rials being removed contain toxic substances, additional protection may be required.

" Hearing protection: Recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-23

_Section ZOO 41*11, 1 N'r r iNATIO N A L he CONCRETE REPAIR N S T I T U T E EC 75219 Page 26 of 43

,"noLU; M115MV[ UU0 l0K, InG.

High and Ultra High-Pressure Water Jetting Water is sprayed at pressures between 5, 000 and 45, 000 psi (35 - 300 MPa) to remove heavy encrustations of dirt and loose, friable material. This method can also remove some coatings.

Method summary This method may be used outdoors to remove heavy encrustations of efflorescence, scale, dirt, or water soluble contaminants from concrete surfaces and sur-face cavities. It may also be used in some interior spaces where heavy mist, spray, high noise levels, and severe puddling can be tolerated. Water jetting, at the higher pressures, effectively removes some coating systems.

Suitable for horizontal, vertical, and overhead applica-tions. This method is not economically suitable for the removal of sound concrete.

Purpose. High and ultra high pressure jetting may be used to remove laitance, efflorescence, scale, dirt, or other water-soluble contaminants. With suitable pres-sures and nozzle tips, high-strength epoxy, urethane, or methacrylate coating and thin overlay systems may be removed. It may also be used to remove carbonated, freeze/thaw damaged, or otherwise weakened material from concrete surfaces.

Limitations. High and ultra high-pressure water jetting is not recommended for the following applications:

" Removal of sound concrete.

" It should not be used where goods or equipment may be damaged by impact from water jets; or where they can-not be protected from heavy mist or flooding.

Removal. Unsound concrete may be removed to depths of 1/4/ -

3/4 inch (6 - 19 mm) and is dependent on the depth of deterioration.

Pattern. Properly done, high and ultra high-pressure wa-ter jetting should not produce any noticeable pattern in durable concrete. However, poor operator technique or inappropriate selection of pressure and nozzle tips may severely etch sound concrete.

Profile. ICRI CSP 6 - 9 The surface profile of durable concrete may remain un-affected by this process' Pressure and nozzle tips may be adjusted to produce the desired profile. The use of high and ultra high-pressure water jetting on low-strength or deteriorated surfaces will produce a much more ag-gressive profile as surface defects are removed.

Accessibility. With the wide variety of portable and ma-neuverable equipment available, most surfaces are eas-ily accessible. Tight spaces can be accessed with a hand-held lance.

The presence of goods or equipment that cannot be ad-equately protected from mist or spray may restrict use of this method.

Environmental factors. This process produces loud noise, similar to sandblasting. Heavy mist and a significant vol-ume of water will be introduced into the work area. The volume of water introduced will range from 2 - 10 gal-lons per minute (3 - 38 liters per minute) and is deter-mined by the requirements of the equipment selected.

The possibility that environmental regulations may re-quire containment and regulated disposal of the liquid waste generated should be considered.

Execution The concrete surface is prepared by methodically mov-ing the water jet back and forth over the surface until 03732-24 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 27 of 43 I N1:

N I" 1

Nr AI _

'3.

CONCRE'V'E REPAIR I- "

r U I" E-

.14' the desired results are achieved. If automated equipment is used, the operator typically makes parallel passes. If hand-held lances are used, the process will be slower, but similar. Standing water may need to be pumped or squeegeed off the surface. Units that clean and recycle jetting water are available. Dispose of solid debris, slurry, and water residue as required by local regulations or project restrictions.

Equipment

- Water pump with desired pressure capability

- Compressed air source producing a minimum of 85 cfm @ 120 psi

- High-pressure hoses

- Water jet: wheeled equipment for horizontal surfaces; hand-held lance for vertical and overhead applications, corners, or. other difficult to reach locations. Robots may be used on horizontal and vertical surfaces.

" Suitable nozzle tip a Runoff protection to catch debris flowing off site or toward drains Materials

• Water source: Potable water is recommended and may be provided by tanker, hydrant connection, industrial spigot, or pump Labor. Two or three person crew per machine. Medium to above medium skill level with appropriate training required. Must be able to assemble high pressure com-ponents and safely operate equipment capable of caus-ing sudden, severe injury. Skilled supervision may be needed if complex equipment is used.

Down time. Setup time is variable depending on the size of the work area and specific protective measures required.

Time to cover and protect surfaces and install runoff pro-tection to catch debris may be estimated at 6 to 10 man-hours for typical applications.

Cleanup. Large volumes of water may need to be drained away. The volume of debris trapped by collectors is usu-ally small. High and ultra high-pressure jetting of dete-riorated surfaces may produce much more debris.

Production rates. The rates shown below are approxi-mate and assume sound, 5,000 psi (35 MPa) concrete.

Actual production rates will vary considerably and will depend on the strength of the concrete, hardness and bond strength of any coating being removed, preparation ob-jectives, operator skill, and efficiency of equipment employed.

" Horizontal surfaces: 125 - 300 ft2/hr (12 - 28 m2/hr)

• Vertical surfaces: 50 - 250 ft/hr (5 - 23 m2/hr)

Standards h specifications As required by the specifications of the manufacturer or customer.

Visual inspection should show no dirt, laitance or debris on the surface. The prepared surface should be free of bond-inhibiting barriers and demonstrate sufficient strength for the proposed application. Beads of water indicate a surface contaminant that may require increased depth of removal to achieve suitably clean surfaces. ACI 515.1R describes methods and criteria for judging sur-face cleanliness and strength (see ref. page 41). Labora-tory testing may be required to verify complete removal of specified contaminants.

Safety The operator must be protected from high velocity re-bound. Hands and feet require additional protection as they might inadvertently contact the water jet.

" Eye protection: Anti-fog goggles meeting ANSI re-quirements for high impact, and face shield.

" Personal protective equipment: Metal-mesh gloves are strongly recommended, steel-toed boots, metatarsal guards, helmet, and waterproof outer-layers.

" Respiratory protection: May be required in areas where high impact could cause an accidental release of toxic substances,

" Hearing protection: Process will generate noise levels in excess of 85 dB. Earmuff type protectors strongly recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-25

Ition ZOO k IA~NTIE FlNATION AL

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CONCRETE REPAIR

• lil, JI N S T I I

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EC 75219 Page 28 of 43 rilviv; 1UPIUI lVlU~lll'..

it Scabbling Impacting the substrate at right angle with piston-driven cutting heads to create a chipping andpowdering action. The driving mechanism is compressed air Method summary Scabbling is used primarily on horizontal surfaces to remove concrete or brittle coatings up to 1/4 inch (6 mm) thick. It may also be used to deeply profile concrete sur-faces. Hand-held units, some of which are commonly known as "bush hammers," are available for light ser-vice on vertical and overhead surfaces. This method is suitable for use in interior and exterior applications.

Purpose

" The removal of brittle coatings such as epoxy, poly-urethane, or methyl methacrylate systems up to 1/4 inch (6 mm) in preparation for overlays over 1/8 inch (3 mm) thick.

• Removal of deteriorated or contaminated concrete to depths ranging from 18 to 3/4 inch (3 - 19 mm) depend-ing upon the strength of the substrate, size and power of the machine, and bit configuration.

" Deep profiling of concrete surfaces in preparation for placement of overlays or other repair materials.

Limitations

• Scabbling frequently causes micro-cracking in concrete substrates. (It has been demonstrated that micro-crack-ing will reduce the strength of the bond between the substrate and most materials placed over it.) The del-eterious effects of micro-cracking may be reduced or eliminated by following initial removal with steel shotblasting, abrasive blasting, or high and ultra high-pressure water jetting.

• Scabbling is not recommended for the removal of elas-tomeric membranes or gummy materials such as tile or carpet adhesives.

Removal. Depth of economical concrete removal is de-pendent on aggregate size and strength of the substrate and may range from 1/s to 3/4 inch (3 - 19 mm).

Pattern. Scabbling will produce a very irregular surface dominated by fractured coarse aggregate. There should be no discernible tool pattern.

Profile. ICRI CSP 7 - 9 Accessibility. With portable equipment ranging in size from small hand-held to large walk-behind units, most surfaces are accessible to the edges. Corners, recesses, and tight configurations are generally accessible with properly-sized bits fitted to hand held, single piston units.

Care should be taken to avoid damage to adjacent walls or equipment.

Walk-behind units will pass through standard door open-ings and will require a minimum vertical clearance of 4 feet (1.2 m).

Environmental factors. Scabbling will produce airborne dust containing concrete constituents and particles of any other materials being removed. Any special requirements for containment and disposal of dust and debris will de-pend on the specific materials or contaminants being re-moved. Materials likely to require special handling in-clude tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electrical equipment. Noise levels are likely to exceed 85 dB. Vibration levels are moderate to severe. Work area enclosures and special ventilation provisions may be required indoors to pre-vent dust intrusion into nearby occupied work space.

03732-26 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 29 of 43 iN s, -v i r

t -Trý i-i Execution Scabblers are operated by manually pushing the units across the surface in a back and forth motion at slow speed. The area being scabbled will require continuous sweeping to allow the operator to see the removal progress.

Equipment

" Scabbler: manually-operated machines range from single-head, hand-held units to walk-behind units hav-ing up to twelve heads

• Air compressor or other air source producing a mini-mum of 180 cfm @ 120 psi. Cfm requirements are likely to increase with larger equipment and multiple heads. (Disregard air requirements if hydraulic scabblers are used.)

• Air hose: V2 - 2 inches (13 - 50 mm) I.D.

Materials. Impact bits are the consumed material. These are available in varying configurations of tungsten car-bide inserts.

Labor. Operator skill requirements are considered low.

Down time. Minimal. Setup requires very little time, un-less dust protection includes draping and taping. Setup of air hoses and changing bits is required once per day.

Bit changes will take anywhere from 10 minutes for single-head units to as much as 35 minutes for large, multi-head units. Scabbler machines require little main-tenance.

Cleanup. Dust and larger particles up to /2 inches (13 mm) in diameter will be generated from the impact of the bits. Scabblers are rarely equipped to pick up this debris. Sweeping and vacuuming will be continuously required to remove the rough debris and fines.

Production rates. Productivity will vary considerably depending on size of machine, strength of substrate, depth of removal, and the type of material being re-moved. For heavy removal, estimated rates range from 20 ftWhr (2 m/hr) to 100 ft2/hr (9 m2/hr).

Standards i specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, or bond-inhibiting barriers, and demonstrate sufficient strength for the pro-posed application. ACI 515.1R describes methods and criteria for judging surface cleanliness and strength (see ref. page 41).

Safety

" Eye protection: Required.

" Personal protective equipment: Skin should be pro-tected by clothing and barrier creams. Dust may pro-duce alkali burns or allergic skin response.

" Respiratory protection: Required. Mask should be ap-proved for silica and other airborne dusts, and fit tightly to contours of face. If materials being removed contain toxic substances, additional protection may be required.

" Hearing protection: Recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-27

"on ZOO I0~\\NTERNATIONAL CONCRETE REPAIR I NS I TU T 1 EC 75219 Page 30 of 43 rijULU; % t,1I.Ul [U.IdU IIIIJ Ito.

Flame Blasting The combination of oxygen and acetylene to produce aflame which is passed at a given height and rate over the substrate.

Method summary Flame blasting is used on horizontal, vertical, and over-head surfaces to remove contaminated concrete, mas-tics, or other high-build coatings. The applicability of this method is restricted by the presence of a 3,2000 C (5,8000 F) open flame, and the generation of toxic fumes which may accompany the removal of some materials.

This process does not generate dust and is suitable for interior and exterior applications.

Purpose. To remove elastomeric membranes, paints, coatings up to '14 inch (6 mm) in preparation for the ap-plication of overlays over 1/o inch (3 mm) thick. Flame blasting may also be used to remove grease and oil contaminants.

Limitations. This method may not be used in the vicinity of flammable or combustible materials. It will generate a heavy volume of smoke and fumes when used to re-move membranes, coatings, and other hydrocarbons from the substrate. Flame blasting may produce micro-crack-ing. Although some bond strength testing suggests that the process does not cause micro-cracking, the data are insufficient to be conclusive. (It has been demonstrated that micro-cracking will reduce the strength of the bond between, the substrate and most materials placed over it.) The deleterious effects of micro-cracking may be re-duced or eliminated by following initial removal with steel shotblasting, abrasive blasting, or high and ultra high-pressure water jetting.

Removal. Removal is accomplished by the superficial fracturing of the substrate induced by the expansive force of superheated pore water. Depth of removal ranges from VI - 1/4 inch (3 - 6 mm) per pass.

Pattern. Flame blasting will produce an irregular, chipped surface with no discernible pattern.

Profile. ICRI CSP 8 and higher Sharp angular surface with a profile amplitude ranging from 1/s - 11/44 inch (3 - 6 mm).

Accessibility. The equipment is relatively small and highly maneuverable. A hand-held torch connected to the fuel source with flexible hoses provides unrestricted access to include edges, corners, and recessed spaces.

However, access may be restricted by the presence of combustible adjacent surfaces, or non-portable machin-ery or equipment.

Environmental factors. Flame blasting will generate hot, flying debris capable of igniting combustible materials in the vicinity of the process. The acetylene-oxygen com-bustion products are not hazardous. However, the heat of the flame may generate smoke and fumes which may be respiratory irritants or toxic, depending upon con-taminants present in the substrate or materials being re-moved. Materials likely to pose a respiratory hazard and require special handling include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of elec-trical equipment. It is probable that the risk factors posed by the vaporization of contaminants or materials being removed cannot be reliably accessed in every instance.

In these circumstances, the prudence and utility of using this method would need to be very carefully considered.

Execution Concrete surfaces to be cleaned and profiled by this method must be presoaked for one to two hours to pro-ii 03732-28 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 31 of 43 SsINFR3fN.ATIONAL I N1 S; T 1 U "

duce saturated, surface dry conditions. This step is re-quired to insure that the substrate contains enough mois-ture to generate the expansive force required to fracture the surface.

Equipment

" Specialized equipment designed to shape the flame, positively control fuel sources, and project the flame onto the substrate is required

" Sufficient hose to transport fuel from the storage loca-tion to the work area Materials. Acetylene and oxygen are the consumed mate-rials. These industrial gases must be available in appropri-ate containers.

Labor. Operators must be trained by the manufacturer of the equipment and-skilled and knowledgeable in the handling of oxygen-acetylene mixtures. Operators must know when and how to use high temperature open flames and which materials are hazardous when they bum or decompose under heat.

Down time. Minimal. Some time is required for setup and changing tanks.

Cleanup. Flame blasting produces debris consisting of concrete chips. If the substrate was protected by a coat-ing or other barrier system, the chips may be covered with a charred polymer residue. Debris may be removed with oil-free air blast or by mechanical or manual sweep-ing with stiff-bristled brushes.

Production rates. Rates depend on the thickness and composition of the materials being removed, the num-ber of flames, and the rate of travel. Estimated rates range from 50 - 600 ft?/hr (5 - 55 mlfhr).

Standards I specifications As required by the specifications of the manufacturer or customer.

Visual inspection to verify profile. The prepared sur-face should be free of dust, debris, bond-inhibiting bar-riers, and demonstrate sufficient strength for the pro-posed application. ACI 515.1R describes methods and criteria for judging surface cleanliness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of specified contaminants.

Safety Flame blasting will induce the explosive fracture of ag-gregate which may propel hot, airborne fragments as far as 20 feet (6 m).

" Eye protection: Goggles and face shield meeting ANSI requirements for high impact resistance are required.

Radiant energy shading as recommended by flame equipment manufacturers.

" Personal protective equipment: Helmet and heavy, heat resistant insulating gloves are required. Skin should be protected by heavy, noncombustible clothing and steel-toed boots.

• Respiratory protection: May be required depending upon the composition of materials being removed. It is probable that, at a minimum, the use of masks fitted with organic vapor canisters will be required during the removal of materials containing polyurethane, methacrylate or epoxy compounds.

• Hearing protection: Recommended.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, ANO POLYMER OVERLAYS 03732-29

Section ZOO IN T NR N A? 1 NTION AI-CONCRETE REPAIR I N S T I T U T E

EC 75219 Page 32 of 43 rnoio: Lammoro roiners uompany, inc.

Milling/Rotomilling An aggressive method for removing the upper level of a concrete substrate by "clawing" or grooving using a large machine with cutting teeth attached to a rotating drum.

Method summary Milling is used on horizontal surfaces to remove unsound concrete, mastics or other high-build coatings, and as-phaltic overlays. It may also.be used to deeply profile concrete substrates. This method is suitable for use in interior and exterior applications.

Purpose. Heavy-duty removal of deteriorated concrete and virtually any overlay, coating, or mastic materials in preparation for the placement of protective overlays.

Limitations. Slabs must be structurally able to support large, heavy equipment. This method will produce high levels of noise, dust, and severe vibration.

Milling operations will probably cause micro-cracking.

(It has been demonstrated that micro-cracking will re-duce the strength of the bond between the substrate and most materials placed over it.) The deleterious effects of micro-cracking may be reduced or eliminated by fol-lowing initial removal with steel shotblasting, abrasive blasting, or high and ultra high-pressure water jetting.

Removal. The cutting teeth strike the surface with great force, fracturing material into chips and dust. Depth of concrete removal ranges from 11/4 - 4 inches (6 - 100 mm). Removal depth is determined by the number and size of teeth. Smaller teeth in greater numbers are used when shallow removal depths are desired. Most machines are equipped with depth gauges which allow the opera-tor to limit the depth of cut.

Pattern. Milling will produce a very irregular surface dominated by fractured coarse aggregate. A tool pattern will range from linear striations to deep grooving.

Profile. ICRI CSP 9 Extremely rough, chipped surface with a profile ampli-tude ranging from 1/414 1/2 inches (6 - 13 mm). Profile obtained is determined by the number and size of teeth.

Accessibility. Most milling equipment will reach to within 6 inches (150 mm) of walls, and 12 inches (300 mm) of corners. A vertical clearance of approximately 6 feet 8 inches (2 m) is required. Turning radii will need to be plotted to determine if there is sufficient space for maneuver around columns, wall, and corners. Shoring of supported levels may be required.

Environmental factors. Milling will produce airborne dust containing concrete constituents and particles of any other materials or contaminants being removed. Any spe-cial requirements for containment and disposal of dust and debris will depend on the specific materials or con-taminants being removed. Materials likely to require spe-cial handling and disposal include tile mastics, which may contain asbestos; lead-based paint; and PCBs which may have been absorbed by concrete in the vicinity of electrical equipment. Work area enclosures to prevent dust intrusion into occupied work space may be needed.

Special ventilation provisions may be required when op-erating gasoline or diesel powered units indoors.

If water is used to control dust or clean the substrate, the run off will have a high pH and may contain regulated substances. Filtration systems or settlement tanks may be needed in conjunction with drainage systems to meet environmental requirements.

Noise levels will exceed 85 dB. Vibration levels are severe.

2J 03732-30 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 33 of 43 I

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.Cr-Execution

" Milling equipment is driven in a straight path.

" Depth is controlled by observing depth gauge. Mul-tiple passes may be required.

" Each pass must overlap the adjacent pass.

• Debris is removed from the site.

Equipment

" Milling machine (transported by tractor and low-bed trailer with ramp)

" Debris removal equipment may include dump trucks, loader, conveyor system, shovels and brooms

" Shoring devices may be required to support machine weight on elevated slabs Materials. Milling heads or "teeth."

Labor. Experienced, trained machine operators are needed to operate equipment and perform periodic main-tenance or replacement of cutting heads. Additional Workers with appropriate skills are needed to operate the support equipment such as conveyors, dump trucks, and for general clean up.

Down time

" Job site must be prepared to receive equipment. Elec-trical hazards, structural capacity analysis, environmen-tal requirements, and safety issues must be addressed prior to machine operation.

" Mobilization of the equipment onto the surface, instal-lation and adjustment of cutting heads, and dust/de-bris control equipment.

" Smaller work areas may require equipment to be shut down at 30 minute intervals for debris removal.

" Periodic inspection, adjustment, or replacement of cut-ting heads or drive train components is required to maintain specified cutting depth and profile. Replace-ment of cutting heads is generally needed every 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> of operating time.

Cleanup. Chips and dust may be removed with water, air, brooms, or shovels. Self-propelled sweepers are com-monly used.

Production rates. Estimated rates are listed below:

• 1000 ft2/hr (90 m2/hr) for small machines

• 3000 - 4000 ft2/hr (280 - 370 m2/hr) for mid-range machines

• 15,000 ft/hr (1400 m2/hr) for large highway machines Standards & specifications Milled substrates are visually inspected to confirm com-pliance with specifications for profile and depth of re-moval. The prepared surface should be free of dust, de-bris, bond-inhibiting barriers, and demonstrate sufficient strength for the proposed application. ACI 515.IR de-scribes methods and criteria for judging surface cleanli-ness and strength (see ref. page 41). Laboratory testing may be required to verify complete removal of speci-fied contaminants.

Safety

" Eye protection: Required.

" Personal protective equipment: Skin should be pro-tected by clothing and barrier creams. Dust may pro-duce alkali burns or allergic skin response.

" Respiratory protection: Required. Process will gener-ate airborne dust. Mask should be approved for silica and other airborne dusts, and fit tightly to contours of face. If materials being removed contain toxic sub-stances, additional protection may be required.

" Hearing protection: Required.

/

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-31

Section ZOO EC 75219 Page 34 of 43 N

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CONCRETE REPAIR I N s t

T U T E Appendix A The Method Selection Process The initial step in the selection process is to determine project objectives and requirements. Consistently good Method Selection Process J preparation decisions cannot be achieved without a thor-ough understanding of the material requirements, sub-strate conditions, and the owner's objectives and oper-CoSabtrat ating needs. Because the surface preparation method(s) conditions requirements used will determine the substrate profile, consideration of methods should be deferred until after the coating Detercine system has been selected and film thickness requirements are known. It is only after performance requirements have been identified and prioritized, and selection crite-Project Owner Application ria have been defined, that the selection of specific meth-Analysis requirements ods of surface preparation can be made.

The checklists which follow in Section I help ensure Determine that critical information is identified and considered on and priorltize every project. The data generated in the evaluation phase performance criteria are analyzed to identify project priorities and to develop criteria for the selection of surface preparation meth-ods. This phase is discussed in Section 2. Examples of need prioritization are included to underscore the fact Identify that selection decisions will be driven by a series of trade-methods which will offs. Once project requirements, priorities and selection provide required criteria have been determined, the Method Summaries Preparation performance and Method Selector (pages 7 - 31)'may be used to iden-Strategy tify the method, or combination of methods, most likely to produce the desired results for that project. The Select method(s) that Method Selector may be used to quickly match typical provides optimum balance of coating system requirements and methods capable of performance, risk, and cost factors producing the required profile. The factors which should shape the selection decision are reviewed in Section 3.

03732-32 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 35 of 43 I N* T E R1 N A'f' 101 NA LaI NA Ind

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Appendix A Section 1 Determine project objectives and requirements The information gathered in this phase is needed to de-velop specific criteria for determining which method or Method Selection Process combination of methods will best meet the engineer's and owner's objectives. Checklists on the following pages provide examples of the data needed to identify OwnerMaterial and prioritize performance requirements.

requirements requirements 1 Substrate condition-The strength of the substrate 7

and the presence of unsound or bond-inhibiting ma-terials help define the nature and volume of prepara-

[

J tion needed. Although a discussion of the various techniques and test methods used to evaluate the con-Substrate Application dition of concrete is beyond the scope of this guide-ConditionsI line, the checklists provide examples of the types of information which should be considered.

Determine 2 Owner requirements: Noise, vibration, dust, and wa-and prioritize ter are among the possible effects generated by vari-performance criteria ous preparation methods. These can disrupt routine use of the structure or damage its contents. The owner's need for uninterrupted use of the structure, concerns about the operating environment, or prop-Identify erty damage potential will often limit the choices.

methods which will provide required 3 Material requirements: Good decisions about sur-performance face preparation cannot be made without knowing the properties and application requirements of the se-lected material. Surface preparation, and profile re-quirements in particular, will vary with the protec-Select method(s) that tive system selected. Ideally, the protective coating provides optimum balance of system to be applied should be selected before or performance, risk, and cost factors during this phase. The short description of these broad coating categories provided in Appendix B help il-lustrate the effect substrate profile may have on the performance and appearance of these systems.

4 Application conditions The generation of dust, slurries, or large volumes of water may introduce requirements for their contain-ment and safe disposal. The type and capacity of me-chanical ventilation and available power sources, the size of door openings and minimum vertical clear-ance are all examples of application conditions which will affect surface preparation decisions.

The checklists will help ensure that the most important issues will be considered and resolved at the optimum time-before the project is underway.

SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-33

Section ZOO EC 75219 Page 36 of 43 INTER NATIONAL CONCRETE REPAIR IN S T I T U T E

Appendix A Substrate Condition Method Selection Process SurfaceCotn Irequirements Soill/Efflorescence/Encrustation Determine Type project objectives Thickness Owner Application Bond strength requirements conditions Surface imperfections Dr and prioritize O laitance 3 bugholes El ridges

[3'exposed aggregate 173 abrasion performance criteria O other I

Bond-breaking contaminants El oil 0 membranes

[3 coatings El curing films 17] latex modifiers methods which will provide required C3 other performance Soundness Son s Select method(s) that Deteriorated concrete depth provides optimum balance of performance, risk, and cost factors Cause Pull-off test results Chloride content Hazardous materials present 13 PCB 0 asbestos mastic El pesticides C3 chemicals 13 heavy metals C3 other Special containment or disposal required General observations Permeability (inhibit penetration)

Section thickness Required depth of removal Moisture content I

03732-34 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 370of43 RigfIN 'ST I

U TE

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Appendix A Owner Requirements Project objectives Appearance of applied system Texture:

r smooth 0 slip-resistant 0 reflect substrate contours Opacity:

C clear 0 translucent 0 solid color Structure utilization needs Work period methods which will hours _duration provide required hoursduraion erfomanc Negative effects

?

noise water/slurry dust smoke & fumes Select method(s) that provides optimum balance of vibration flying debris performance, risi, and cost factors I OMMM.M..10 Material Requirements Substrate Tensile strength (ICRI No. 3735 ACI 503 Appendix A)

Surface profile acceptable range (CSP numbers)

Material Film thickness wet:

dry:

Moisture tolerance Alkali tolerance SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-35

INTEFINATIONAL 1otBSCONCRETE REPAIR (N i ir0 N S TI T uIF'-

EC 75219 Page 38 of 43 Appendix A Application Conditions Accessibility Surface orientation 0 horizontal (3 vertical E overhead turning radius __

door openings __

min. vertical clearance load-bearing capacity non-portable equipment/machinery notes Environmental considerations containment of airborne debris containment and disposal of liquid/slurry debris drainage system restrictions on use containment and disposal of solid debris hazardous waste containment and disposal Mechanical data Electricity types available locations Air maximum pressure available cfm locations Ventilation natural mechanical 03732-36 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 39 of 43 tt I

,r FiN AT O N A L N

CONCRETE R1PAIR IF I INrTITL)TE Appendix A Section 2 Establish performance priorities Surface preparation methods should not be specified until the performance criteria which best satisfy project ob-jectives are identified. Information on existing condi-tions, requirements, and project objectives collected in the evaluation phase is used to develop performance cri-teria, which are then prioritized. These should be ranked in descending order of importance. Objectives and re-quirements that are not essential should not be listed.

This process allows competing demands to be carefully weighed to ensure that the performance criteria most critical to the success of the project become the selec-tion criteria. Two sample lists are shown below:

Example 1: Interior floor replacement A 30 x 70 foot (9 x 22 m) room in a large production facility is to be converted from shipping into an elec-tronic components assembly area. The existing 1/8 inch (3 mm) aggregate-filled MMA floor is to be replaced with an epoxy, antistatic conductive floor coating. The conductive floor will be installed during a 96 hour0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> facil-ity shut down. Dust must not circulate in the climate-controlled building. A surface profile of CSP 2 - 3 is required to ensure fiber continuity in the base coat.

Priorities: (ranked in order of importance) 1 Achieve CSP 3 or lower to meet floor system require-ment to ensure conductive function.

2 Dust-free preparation in order to preclude product quality problems 3 Fast turn-around to complete project within shut down window 4 Low vibration to maintain calibration of sensitive in-strumentation Example 2 Deck coating installation A 240 stall structure providing employee parking for general hospital is to be protected by a traffic bearing membrane. Surface preparation must remove all dete-riorated concrete, bond-inhibiting contaminants, and leave deck surfaces with a profile within a range de-fined by CSP 3 - 4. The parking structure has a com-Identify methods which will provide required performance Select method(s) that provides optimum balance of performance, risk, and cost factors I mon shear wall with patient rooms for two of its four levels. The hospital requires that 85% of parking capac-ity remain in service throughout project.

Priorities: (ranked in order of importance) 1 Dust-free preparation to prevent finish damage to parked vehicles 2 Low noise/vibration to minimize patient discomfort 3 Achieve profile CSP 3 or 4 to provide optimum sur-face for bonding 4 Fast turn around to minimize employee inconvenience SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS 03732-37

• on ZOO (k

INTrEF*NATIONAL JI[CONCRET RPAIR IN S T1 TU T N Appendix A Section 3 EC 75219 Page 40 of 43 EC 75219 Page 40 of 43 Selecting and specifying methods of surface preparation Most coating or sealing projects will have unique con-ditions and special requirements that must be carefully evaluated before the selection criteria can be established.

Selecting the method(s) which optimize project objec-tives requires a good knowledge of the available options.

The Method Summaries and Method Selector contained in this guideline (pages 7 - 31) allow users to readily compare data on the capabilities, limitations, operating requirements, and environmental considerations for each surface preparation method. Using the performance cri-teria developed earlier (Sections I and 2), the number of suitable methods is likely to be quickly narrowed to 1 - 3 potential selections. The Method Selector (page 7) may be used make a preliminary identification of the methods capable of producing the required surface pro-files. In some cases, however, specific project conditions may preclude the use of the methods suggested.

Careful evaluation of competing priorities will be re-quired to determine the best selection. Selection criteria provide a systematic framework for assessing method suitability and guide decisions when compromise is needed to ensure achievement of the most important project objectives.

In some instances, more than one method may be needed to produce the desired results. For example, high impact' mechanical methods which produce surface "bruising" may sometimes provide the most efficient means of achieving the required degree of cleaning. In these circumstances, subsequent treatment with shot or abrasive blasting, fine scarification or high and ultra high-pressure water jetting may be used to restore sub-strate soundness. In another example, the most cost ef-fective approach to surface preparation may include the use of a method which produces a high profile in the substrate. Material consumption on prepared concrete surfaces is influenced by several factors including sub-strate surface area, porosity, waste, uniformity of film thickness, and the volume of material needed to fill in

)

r Select method(s) that provides optimum balance of performance, risk, and cost factors surface depressions caused by profiling. If necessary, unacceptably high or rough profiles on existing or pre-pared surfaces may be reduced by means of additional passes usifig properly selected surface preparation equip-ment. On occasion, the application of a resurfacing mor-tar or leveling film of a coating material compatible with the system to be applied may be required to achieve the profile and appearance desired.

Final selection is based on the relationship between cost, project objectives, and risk.

Si 03732-38 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

• f,.*

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Section ZOO A N/

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C ? N A ' r T 1 -0 N.A.

, 9145tl" CNCRETC RI.PAKI1 Appendix B Sealers and coatings Concrete sealers 0 - 3 mils (0 - 75 gtm) dry Penetrating sealers such as silanes or siloxanes will have little or no effect on the appearance of the treated sur-faces. Any surface defects, contaminants, or profile will be visible. Film-forming sealers such as epoxies, ure-thanes, and acrylics, in unpigmented formulations may substantially darken concrete and impart a sheen. Lack Penetrating sealer of hiding power is comparable to that of the penetrating sealers. Pigmented formulations may hide stains and impart a degree of light reflectivity; however, surface irregularities and profile will not be altered.

Thin-film coatings 4-10 mils (100-250p m) dry These products may be formulated to achieve high hid-

,I ing power. However, even relatively minor surface im-perfections and all but the lowest of profiles produced by surface preparation equipment will show through.

Thin-film coating High-build coatings, self-leveling coatings, and polymer overlays 10 mils - 1/4/ inch (250 gxm - 6 mm) dry The selection of these materials for application provides the specifier with many more preparation options. These materials will have both high hiding power and some ability to fill in irregularities and level prepared surfaces.

The contractor's ability to produce a smooth finish over H-ldcai or higher profiles improves with increasing thickness of the applied coating system.

SELECTING AND SPECIFYING CONCRETE SiIRFAr.F PRrPaRATnft rnR 'ZAI CD ('fArIKflO A~~ Dn,,.-, Ml,-..

.Slection ZOO EC 75219 Page 42 of 43 IN NrEnNATION/AL f

CONCRETE REPAIR SI N ST I T U TE Appendix C Safety Safety implications anticipated for each method are in-cluded in the Safety section of the method summaries.

The information is intended only to alert users to the nature and magnitude of the safety issues associated with the method described.

Referenced OSHA regulations apply to typical haz-ards that may reasonably accompany a selected method of surface preparation. Additional regulations may ap-ply depending on the work area conditions and jurisdic-tion. Consult a safety professional or OSHA about ap-plicable regulations.

For further information, refer to the OSHA regu-lations that pertain to each of the protection catego-ries referenced in the method summaries. Included therein are detailed references to safety protocols equipment standards, personnel training, and docu-mentation needed to meet OSHA requirements.

)'

03732-40 SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, AND POLYMER OVERLAYS

Section ZOO EC 75219 Page 43 of 43

/N01ý~ I N' F FýN 011A1 Appendix D References and Related Material American Concrete Institute. Annual. Manual of Concrete Practice, Five Parts, Detroit, MI, "Guide to the use of Waterproofing, Damp-proofing, Protective, and Decorative Barrier Systems for Concrete," ACI 515.IR, Chapter 3, Concrete Conditioning and Surface Preparation. (note in particular: Section 3.5 "Tests for surface quality prior to application")

ASTM American Society for Testing and Materials.

Annual. Annual Book of ASTM Standards, Philadelphia, PA. Note: Use the latest available issue of each ASTM standard.

ASTM D 4258 Standard Practice for Surface Cleaning Concrete for Coating This practice defines methods of cleaning concrete to remove grease, dirt, and loose material prior to the application of coatings. The procedures outlined in the standard include: broom cleaning, vacuum cleaning, air blast cleaning, water cleaning, detergent water cleaning, and steam cleaning of concrete surface for applying coatings for light duty service. Broom cleaning:

is to remove most surface dust and other loosely adherent solid contaminants. Vacuum cleaning: removes dust and other debris by the use of a heavy duty industrial vacuum.

Air blast cleaning: uses compressed air and abrasive at 80 to 100 psi through a blast nozzle held approximately 2 feet from the substrate. Water cleaning: uses a stream of clean potable water of sufficient pressure to remove debris. Hand scrubbing with stiff-bristled brush may also be required.

Detergent water cleaning: the removal of water-soluble surface contaminants, oils, grease, and other emulsifiable materials using a detergent or non-solvent emulsifier and stiff-bristled brush. Steam cleaning: uses a jet of high-pressure steam to remove contaminants. Detergents or non-solvent emulsifying agents may be added to aid in removal.

Areas where detergents or non-solvent emulsifying agents are used must be flushed with potable water to meet an acceptable criteria for pH. An acceptable surface after cleaning of concrete by one or more of these methods shall be a substrate free of oil, grease, loosely adhering concrete, and other contamination.

ASTM D 4259 Standard Practice for Abrading Concrete This is a standard practice to provide a clean and roughened surface that is free of laitance, form release agents, curing agent, oil, grease, and other penetrating contaminants. The surface shall be free of fins, projections and loosely adhering concrete, dirt, and dust particles. Suitable methods include: using rotary impact, vertical impact, and circular grinding equipment; Water blast cleaning: using a high pressure water blasting unit and fresh potable water; Abrasive blast cleaning: including wet or dry open-blast cleaning with nozzles and self-contained recirculating blast-cleaning apparatus.

ASTM D 4260 Standard Practice for Acid Etching Concrete The intent of this practice is to prepare concrete surfaces prior to the application of coatings by altering the surface profile and removing foreign materials, such as weak surface laitance. All grease, oil and other penetrating contaminants should be removed prior to acid etching. Fins and protruding surface irregularities are to be removed by mechanical means. Typical acid solutions covered by this method include: muriatic (hydrochloric), sulfamic, phosphoric and citric acids. Note: Hydrochloric acid shall not be used where chlorides are prohibited. The acid solutions are applied to a surface that has been pre-wetted with potable water. After scrubbing with a stiff-bristle brush, the surface is flushed with fresh potable water to remove reaction products.

ASTM D 4262 Standard Test Method for pH of Chemi-cally Cleaned or Etched Concrete Surfaces This test method is used when chemical cleaning or acid etching has been employed to prepare concrete surfaces for coating.

The acidity or alkalinity of the final rinse water is measured using pH test paper with a minimum range of from 1 to 11 pH. Measurement of at least two areas in each 500 square feet at random locations is required. The final pH reading shall not be more than 1.0 lower or 2.0 points higher than the original pH of the rinse water unless otherwise specified.

ASTM D 4263 Standard Test Method For Indicating Moisture in Concrete by the Plastic Sheet Method This test method indicates the presence of capillary moisture in concrete by taping a plastic sheet 18 inches square to the surface to be coated. The test should be conducted when the ambient conditions and surface temperature are within the established parameters for application of the specified coating system. The plastic is to remain on the substrate for a minimum of 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />. Upon removal, the area is inspected for the presence ( or absence) of moisture.

ASTM D 4285 Standard Test Method for Indicating Oil or Water in Compressed Air This test method uses either an absorbent or nonabsorbent collector that is positioned 24 inches in front of the discharge air after any in-line oil and water separators. After a period of not less than 1 minute, the collector is inspected for indications of oil discoloration or water, SELECTING AND SPECIFYING CONCRETE SLURFAr.F PFP*nA.TInN FnR RFAI FS, rnATIKIe' A hin PniVRAg* nAca Ir A

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Section Z01 EC 75219 Page 1 o TECHNICAL.

.GUIDELINES Prepared by the International Concrete Repair Institute October-1989 (reissued March 1995).

Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion Guideline No. 03730 f 7 Copyright © 1995 International Concrete Repair Institute All rights reserved.

International Concrete Repair Institute 3166 S. River Road, Suite 132, Des Plaines, IL 60018.

Phone: 847-827-0830 Fax: 847-827-0832 Web: www.icri.org E-mail: info@icri.org 917

B Page 2 of 7

,91.8 Section ZO1 CONCRETE EP A ANUAL Technical Guidelines Committee Committee members during the preparation of the 1989 edition:

Peter H. Emmons, Chair Structural Preservation Systems, Inc.

Baltimore, Maryland, Kermit D. Bright Structural Engineering Associates Kansas City, Missouri, Richard P. Delargey Structural Maintenance Systems, Inc.

Exton, Pennsylvania Don Gardonio Facca Constructionln'c:-

Maidstone, Onpafio, Canada Robert Tracy Tracy Restoration Engineers Ann Arbor, Michigan Douglas G. White Thomas Downey, Ltd.

Arlington, Virginia Current committee members who provided further input for the 1995 edition:

Peter H. Emmons, Chair Structural Preservation Systems, Inc, Baltimore, Maryland Tom Kline Structural Preservation Systems, Inc.

Gilberts, Illinois' James E. McDonald Waterways Experiment Station Vicksburg, Mississippi Jack A. Morrow Jamor Engineering Calgary, Alberta, Canada Ken Lozen.

NTH Consultants, Ltd.'

Farmington Hills, Michigan Robert R. Cain KRC Associates Milford, Ohio

• 1

~U

Section Z01 SURFACE IFI ATION GUIDE Page 3 of 7 919 Introduction This document is the result of a process of distribution, commentary, and revision by the Technical Guidelines Committee and the member-ship of the International Concrete Repair Institute. It was submitted to the voting members of the Association for approval on August 1, 1989, and approved by over 95% of the respondents.

Several of the comments of the voting members, both from those who voted for approval and those who voted against approval, are worth noting and are reprinted below.

0 Even though a guideline exists for determining the amount of allowable corrosion before replacing or supplementing a reinforcing bar, it is always wise to consult a structural engineer if any corrosion exists.

Special caution should be taken to locate and avoid buried electrical conduits or prestressing or post-tensioning tendons when performing removals. Cutting into either can be a life threatening situation.

Undercutting the reinforcing bar should not be counted on to secure the repair structurally in lieu of proper methods of bonding a repair to the existing substrate.

• A sawcut can and, possibly should, be greater than the 1/2 in. (13 mm) noted, as long as the reinforcing steel is not cut into.

This document is intended as a voluntary guideline for the owner, design professional, and concrete repair contractor. It is not intended to relieve the professional engineeror designer of any responsibility for the specification of concrete repair methods, materials, or practices.

While we believe the information contained herein represents the proper means to achieve quality results, the International Concrete Repair Institute must disclaim any liability or responsibility to those who may choose to rely on all or any part of this guideline.

920 Section Z01

,.Removal Geometry CONCRETE~f9EUM ANUAL Page 4 of 7I' Elevation Section Beam or Rib Column Corner Elevation 4

Slab or Wall Partial Depth

ý.:ý Slab or Wall Full Depth

mu ~r I-Section Z01 SURFACE PREPAPJION GUIDE Page 5 of 7 921 Exposing and Undercutting of", Reinforcing Steel, These details are applicable to horizontal, vertical, and overhead locations. They are also applicable to removal by hydro-demolition, hydro-milling, and elec-tric, pneumatic or hydraulic impact breakers.

0 Remove loose or delaminated concrete above cor-roded reinforcing steel.

0 Once initial removals are made, proceed with the undercutting of all exposed corroded bars. Under-cutting will provide clearaice for-under bar clean-ing and full bar circumference bonding to surrounding concrete kaid will secure the repair structurally. Providý minimum.3/4 inch (19 mm) clearance between exposed rebars and surrounding concrete or 1A inch (6 mm) larger than largest aggregate in repair material, whichever is greater, 0 Concrete removals shall extend along the bars to locations along the bar free of bond inhibiting corrosion, and where the bar is well bonded to surrounding concrete.

o If non-corroded reinforcing steel is exposed.dur-ing the undercutting prpcess, care shall be taken not totdamage ihe bar'.sbond to surrounding concrete. If bond between bar. and boncrete is broken, undercutting of the bar shall be required.

0 Any reinforcement which is loose shall be secured in place by tying to other secured bars or by other approved methods.

922 Section Z01 CONCRETE?&?NWIANUAL Cleaning and Repair of Reinforcing Steel Page'6 of 7 Cleaning of Reinforcing Steel All heavy corrosion and scale should be removed from the bar as necessary to promote maximum bond of replacement material. Oil free abrasive blast is the preferred method. A tightly bonded light rust build-up on the surface is usually not detrimental to bond, unless a protective coating is being applied to the bar'surface, in which case the coating manufacturer's recommendations for sur-face preparation, should be followed.

Reinforcing \\

~Steel

• -Abrasive

~Nozzle Abrasive c c Paths o

corroded Bars Repair of Reinforcing Steel Due to Loss of Section If reinforcing steel has lost significant cross section, a New bars may be mechanically spliced to old bars structural engineer should be consulted. If repairs are or placed parallelrto and approximately '/4 in. (19,mm) required to the reinforcing steel, one of the following from existing bars. Lap lengths shall be determnined repair methods should be used:

in accordance with ACI 318; also refer to CRSI and

• Complete bar replacement, or AASHTO manual.

" Addition of supplemental bar over affected section.

SI Affected Length Loss of Section Required Lap

• I Supplemental Bar Required Lap Affected Length R

U.

Section ZO0 SURFACE PREP/IAT$ON GUIDE Edge and Surface Conditioning of Concrete Page 7 of 7 923

'These details are applicable:.to0horhzntal, vertical, and overhead locatiIns. They ae also applicable to removal by hydro-dernolition,;hydromilling, and elec-tric, 'pheimatic or hydraulic impact breakers.

Do not use these detailsfor shoterete applications-for shotcrete repairs refer to ACi 506Edge Prepara-tion Guidelines.

• Removeý delamninated concrete, undercut rein-

-forcintg steel (refer to "Exposing.'a*id, Undercut-ting of Reinforcing Steel"'on p-age 3), remove additional "concrete as re.uired'toprjovide mim-mumniequired thickness of repi material.

0. At edge locations,.provide right angle cuts to the concrete surface with either. of the following methods:

Sawcut 1/2X".(13,mm)..or less as required to

ýavoid.cutting reinforcing steeL.

".USe power equipment such as hydrodemolition or: impact bre akers. :Avoid feather edges.

O Repair configurations shoutd be kept as simple as possiblej-,prf~rably with*squared corners.

S.After remhovals. and edge conditioning are com-plete, remove. bond: inhibiting materials (dirt, concrete slurrvy, loosely -bonded aggregates) by abrasive blasting or high pressure waterblasting W ih or Without abrasive. Check the concrete surfaces after cleaning to insure thiat surface is free from additionalLoose a-ggregate, or that ad-ditionail delaminations are not present.

(?Jý If hydrodemofitioni is used, cement and particulate slurry must be removedfm the prepared surfaces

.'before slurry hardens.

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Boundary of loose and delaminated Recommended Layout

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Section Z02 - Attachment C EC 75219R0 Page 1 of 4 Designation: D 4580- 03 INTERNATIONAL Standard Practice for Measuring Delaminations in Concrete Bridge Decks by Sounding' This standard is issued under the fixed designation D 45 80; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lasrreappioval. A supirsciipt epsilon (y)' indicates an editorial ch.*igc since the las revision or-rcapprovail.

1 'Scope 1I This practice covers procedures for surveying concrete bridge decks by sounding to determine delaminations in the concrete. It is not intended that the proccdures described herein are to be used on bridge decks that have been overlaid with bituminous, mixtures. The procedures may be used on bridge decks that have been overlaid with portland cement concrete mixtures: however, areas indicated tobe delaminated may have a lack of bond between the overlay and the underlying bridge deck (Note 1).

Nors I-The influence of variable field conditions such as traffic noise, vibration, moisture content of the concrete, and the like. are not com-pletely known ani additional investigation may be needed. It is generally agreed that the practice should not be used on frozen concrete.

1.2 The following three procedures are covered in this practice:

1E2.1 Procedure A, Electro-Mechanical Souhding Device-...

This procedure uses an electric powered tapping deviice, sonic receiver, and recorder mounted on a cart. The cart is pushed acros* the, bridge deck and delaminations are recorded on the recorder.

1.2:2 procedure B, Chain Drag--This procedure consists of dragging a chain over the bridge deck surface. The detection of delaminations is accomplished by the opei'ator noting dull or hollow sounds. Tapping the biidge deck surface with asteel rod or ha.asner may be substituted for the chain drag.

1.2.3 Procedure C, Rotary Percussion2-This procedure consists of rolling a dual-wheel, multi-toothed apparatus at-tached to an-extension pole over the bridge deck surface. The

'This practice is under the jurisdiction of ASTM Committee D04 on Road and Paving 'Materials and is the dir&i responsibility of Subcommittee D04.32 on Bridges and Structures.

Current edition approved July 10, 2003. Published September'2003. Originally approved in 1986. Last previous edition approved in 2002 as D 458.0 - 02.

2-The rotary sounid detecting device. for concrete and procedur aie patent pending in the US,Patent and Trademark Office by Philip K. Clark "Company, Inc.,

503 Central Drive, Suite 102, Virginia Beach, VA 23454. Interested parties are invited to submit informatibn regarding the identificationof an alternaiive(s) to this patent pending item to ASTM Intermational llcadqtiartcrs, 100 Barr Harbor Drive.

PO BoxC700. West Conshohocken. PA 19428-2959. Your comment* Will receive careful consideration at.a meciing of the responsible technical subcommittee,'

which you may attend.

percussive force caused by the tappingwheels will create either a dull or hollow sound indicating any, delamination.

1.3 This stdndard does not purport to address all of the safety concerns, if any, associated with ilts use. It is the responsibility of whoever uses this *andard to consult and establish appropriate saf.,ty and health practices and deter-inine the applicability of regulatory limitations prior to use.

2. Significance and Use 2.1 This practice may be used in conjunction with other methods in determining the general condition of concrete

'bridge decks:

2:2 This practice may be used in determining specific areas of delamination requiring repair.

PROCEDURE A-ELECTRO-MECHANICAL SOUNDING DEVICE

3. Summary of Procedure 3.1 Longitudinal lines at a predetermined spacing are estab-lished on the bridge deck.

3.2 After calibration, the sounding device is pushed along the established lines. Electrically powered-tapping wheels emit vibrations into the deck that are sensed by sonic receivers.

Areas of delamination are indicated by deflections on a strip chart recorder.

3.3 All portions on the strip chart indicating delaminations are plotted on a scaled map of the bridge deck. An outline is made showing the areas of delamination.

4. Apparatus Nom 2-The apparatus described here has been found suiiable and is the most common iype commercially available. Other apparatuses that do not exactly conform to these requirements such as sounding device,

'tapping rate, or sonic receivers may also be accepted.

4.1 Electro-Mechanical Sounding Device-A small, three-wheeled cart upon which is mounted a 12-V battery, two tapping wheels, two sonic receivers, a two-channel-strip re-

'corder, and associated connectors afid cables.

4.1.1 Tapping Wheels-.- Two rigid-steel-tapping wheels ca-pable of tapping the bridge deck surface at the rate of 33 times/s. The tapping wheels shall be located approximately 6 in. (152 mam) apart.

Copyrght © ASTM Internatianal, 100 Barr Harbor Drivo,'PO Box C700, West Conshnhocken, PA 19428-2959, United States.

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Section Z02 - Attachment C EC 75219R0 Page 2 of 4 0-D 4580 - 03 4.1.2 Sonic Receivers-Two sonic receiVers consisting of oil-filled soft tires, inside each of which a receiving transducer is mounted in nonrotating proximity'to the concrete surface.

The transducers shall be piezo-electric hydrophones that are coupled to the concrete surface through the'soft tires and the oil within the wheels: Each receiving wheel shall be. located

-approximately 3 in. (76 mm) outside of and parallel to its corresponding tapping wheel.

4.1:3 Strip Chart Recorder-A two-channel-strip chart re-corder shall be capable of receiving the signals from the sonic receivers.'The electronics unit shall accept only those portions of the signal that occur during ihe first 3 ms after the occurrence of a tap and further limit the recdider 'to respond only to those frequency components of the, signal that lies in the range of 300 to 1200 lIz; The processed signals shall be rectified and integrated to produce a visual record on the respective channels of the record chart. The chart shall be driven in proportion to the distance traveled so that the length of the record represents a predetermined length of trayel. The recording pen on one channel shall be capable of acting as'an event marker.

4.1.4 Cables and Connectors-There shall be sufficient cables and connectors for connection of the left-tapping wheel sonic-receiver system to the left channel of the strip chart recorder and the right-tapping wheel sonic-receiver system to the right channel of the strip chart recorder.

4.2 Measuring Tape, Markers, Stringline --A measuring tape, markers, and stringline shall be provided for establishing lines on the bridge deck that will serve to keep the sounding device positioned properly while making the 'survey.

4.3 Calibrator-A solid alumin.in bar capable of checkihg the operational system of the 'sounding device.

5. Calibration 5.1 Place the device on the calibrator bar in the on position with the chart drive operating. This will establish the electrical zero line.

5.2 With the, calibration switch in the calibrate position, turn on the power, transmitter, and chart drive switches. Eac h of the recorder pens should trace a rather erratic line approximately half way between the maximum pen movement and the electrical zero line. This line may vary one or two major divisions due to norinal variations in the resp6nse of the system to the aluminum bar. If the response line does not fall as described, then each channel shall be adjusted with the appropriate:calibration adjustment control.

6. Bridge Deck Layout 6.1 Any accumulation of debris on the deck must be removed.

6.2 Beginningat a curb face, mark each end of the bridge at the interval chosen -for making the survey.

NO'T. 3-Various spading intervals such asi 5 in. (38.1 6m), 18 in. (45.7 cm), and 3 ft.(91.4 cm) have been used. The closer spacings are recommended For an in-depth analysis of the bridge 'deck. The wider spacing intervals are suitable for generalrcondition surveys of bridge decks.

7T Test Procedure 7.1 Stretch the stringline between corresponding marks on each end of the bridge.

7.2 With the switch in the operate position and the power and transmitter switches on, push the sounding. device at a nonral walking speed over the bridge deck. The device must be centered over the stringline. Continue in this manneruntil the entire deck has been surveyed.

7.3 Mark the ends of the bridge, expansion devices, and so forth, by activating the event marker.

'S. Data Interpretation and Plotting 8.1.. Construct a scaled map of the deck surface.

8:2 Plot the limits of all portions of each trace indicating a delamination. A delamination is considered a trace 'deflection of four -or more minor chart divisions above the nonnal background response.

8.3 Connect the limits of these plots and outline, the indi-vidual delaminated areas.

8.4 Determine the total area contained in the individual dcelaminated areas.

8.5 Divide the total delaminated area by the total bridge deck area and multiply 'times 100 to yield the. percent of deck area delaminated.

PROCEDURE B-CHAIN DRAG

9. Summary of Procedure 9.1 A grid system is laid "out on the bridge deck, 9:2 Chains are dfagged'"ver the deck surface. Delaminated

,areas are those where a dull or-hollow 'sound from the chain dragging operation is apparent.

9:3 Delaminated areas are outlined on the. deck surface. A.

map is prepared indicating thelocation of delaminations with respect to the grid lines, 10.. Apparatus 10.1 Chains, Steel Rods, or Hammers-Acceptable sizes and configurations of chains, steel rods, or hammers ate those that produce a clear ringing sound when dragged or tapped oyer nondelaminated concrete and'a dull or hollow sound over

'delaminated concrete. A common chain drag configuration consists of four or five segments of 1-in. (25-mm) link chain of t..in. (6-mm) diameter steel approximately 18. in. (45.7 cm) long, attached to a 2-ft (61-cm) piece of aluminum or copper tube to which a 2-to 3-ft (61-to 91.4-cmn) piece of tubing, for the. handle, is attached to the midpoint, forming a T. Steel rods 1/ in. by 4 ft (16 mm by 121.9 cm), or largeri have been found to produce satisfactory results.

NorE 4-Heavier chains have generally been shown to.produce a more.

definitive sound under heavy traffic conditions.

10.2'Measuring Tape, Markers, and Stringline-A measur-ing tape,' markers, and stringline shall be provided for estab-lishing a grid system on the bridge deck.-Markers such as spray paint or lumber crayon' shall be used to outline delaminated areas..on the deck surface.

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Section Z02 - Attachment C EC 75219R0 Page 3 of 4 D 4580 - 03 ii. Bridge Deck"Layout 11.1 Any accumulation of debris on the deck must be, remroVed.

1 I2 Construct a grid system on the deck surface with 1a lumber crayon so that. delaminated areas marked on the deck can be plotted easily on a-map by referencing the areas to the, grid.

12. Test Procedure 12.1 Survey the entire bridge deck by dragging The chains or tapping' with the steel rod or hammer over. the entire surface.

On nondelaminated concrete,"aý clear ringing sound will be heard. A dull or hollow sound isemitted When delaminated concrete is encountered.

12.2 Mark the areas of delamination on the deck surface with the spray paint or lumber crayon.

13. Plotting 13.1 Construct a scaled map of the deck surface.

13.2 By referencing to the established grid system on the deck,,plot the areas of delamination on the map.

13.3 Determine the total area contained in the individual delamrinated areas.

13.4 i)ivide the total delaminated area by the total bridge deck area and multiply.by -100 'to yield.thepercent of deck area delaminated.

PROCEDURE C-ROTARY PERCkUSSION

14. Summary ofProcedure 14.1. A grid system is laid, out on the bridge deck, vertical structural support or the, underside of the bridge structure.

14.2 A rotary percussive device is rolled: over the bridge deck, vertical structural member or the undersideof the -bridge deck. Delaminated areas~aYe those areas where a dull or hollow sound is created from the rotary percussion units, striking the surface.

14.3 Delaminated areas are outlined on the bridge, deck's surface, vertical structural surface or on the underside of the bridge deck surface. A map (or field schematic) is prepared indicating the l6cations of the delaminations with respectto the grid lines or with respect to their proximity to permanent structural elements.

15. Apparatus 15.1 Rotary Percussion Sounding DLevice-A "T" shaped device with two rotary percussion units, which spin when rolled over a concrete surface. The-device iseither hand-held or attached to an extension pole to reach-the overhead surfaces-of structural membersor thedtindersid0of the bridge deck surface.

As the rotary percussion sounding device: is rolled over the surface, the two percu.ssion units strike the surface with sufficient force to create either a clear ringing sound when passing over solid concrete-.or a-dull or hollow sound when passing over delaminated concrete.

15.2 Rotary Percus.sion Units-Two hardedehed steel, 15-point percussion unitslare fit onto an axle and -are capable of being rolled over the sUrface to be: tested to, sufficiently :'strike the concrete surface to generate the hollow sound indicative of delaminated concrete.

15.3 Extension Pole --The rotary percussion de'ice is at-tached to a telescoping extensionmpole to reach the surface-to be tested, either the top slab deck or an overhead structural member.

15.4 Measuring Wheel, Markers, anid String Line-A mea-suring Wheel adapted to fit a telescoping extension pole.

Lumber crayons, sprayýpaint markers, and string line shall be used, to establish a grid system so that the delaminated areas caIn be accurately recorded.

16. -Bridge Deck Layout 16.1 Any accumulation of debrisý on the deck inust be removed.

16.2 Constiruct a grid system on the deck surface, vertical structure member, or the underside of the bridge deck with

.chalk line, lumber crayon, or -by the test area's proximity to fixed structural components. Plot the areas on the field sheet.

17. Test Procedure 17.1 Survey the entire deck surface or overhead-structural member by rolling the rotary percussion device ovqer-the entire surface. On non-delaminated concrete, a clear ringing sound will be heard. A dull or.hollow sound will'indicate delaminated concrete.

17.2 Mark the areas of delamination 6n the deck surface with spray paint or lumber crayon: Mark the areas of delami-nation on the vertical structureal members or the underside of the deck structure with an up-spraying spray paint device or lumber crayon.

18. Plotting 18.1 Construct a scale map of'the surface to be tested.

18.2 By referencing-the established'grid system on the deck or overhead surface, plot the areas of delamination on,the map.

18.3 Determine the total delaminaied area within the grid system.

18.4 Divide the total delaminiated area by the total. bridge deck area (or overhead structural element) and multiply by 100 to yield the ipercent:of deck area oroverhead structural element

'found to be delaminated.

19. Report 19.1 The report shall include the following information:

19.1.1 Bridge location and description, 19.1.2 Survey method used, 19.1.3 Date of test, 19.14 Spacing of interval if Procedure A is used, 19.1.5 Percent of deck delaminated, and 19.1L6 Remarks.

-20. Precision and Bias 20.1 The nature of the, methods do not allow for a-round--

robin testing program. Practices do not provide test results, therefofe, no precision. and bias statemenit has been made.

.Nom 5-Availabie data siiggests that the chain drag prbcedureeis mpre precisk in locating dclarnihations than is the elctfmniagietic. soinding device.

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Section Z02 - Attachment C EC 75219R0 Page 4 of 4 D 4580- 03:

ASTMUlntematiohal takes no position respecta.ng the' validity.of'any patent rights asseited in connection with any item mentioned inthis standard. U)sers.oif hisstandard are, expressly advied that deterination of the validity ofany such paterit rights; and the risk of infringement of such rights,,are entirely their own responsibility.

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Section Z03 EC 75219 Page 1 of 28 ACi 503R 93 Reapproved 2008 USE OF EPOXY COMPOUNDS WITH. CONCRETE Reported by Committee 503 H. Akdrige Gillespie Chairman Leonard Pepper Secretary, Russell H. Brink, Belmon" U: Duvall Robert W. Giul Robert F. Kemphues Harold C. Klassen James D7 Kriegh William H. Kuenning Leonard" J. Mitchill' Myles A. Murray G. Michael Scales Raymond J. -Schutz George Sil~dein Frank, Sftiger George W. Whitesides Members?.of-committee v-oting on the 1993 revisions:

Raymond J. Schutz

'Chairman Myles A. Murray Secretary Milton D; Atidrsoni Craig A, Ballinger Roger W. Black F*ank _J Cotntantino John P. Cook-Floyd E, bDimmick Wolfgang Q. Eisenhut' Jack i. Fontana, ARobert W: Gaul Scott "W. Harper Paul-R. Ho611ib'ach David' P. f-lu T.; Michael Jackson Troy D. Madeley Albert Mayer JosePh A. McElroy Paul F.. McHale Peter Mcfidis Richard Montani Richard B' Paimere.

Hamid Saadatmanesh W. Gen~n-Srnok Joe, Solomon Michael M. Sprinkel Robert J., Van Eppsý D: Gerry Walters, Epoxy compounds have found'a :wide.variety of uses in ihe concrete: indus-

.tryai'oatings, grouts,. binde-sY, sealants, bonding agents, patching.mater-ials, and general adhesives.

Rroperiies$ uses,: prepar* iioiS, mixtures, applicati6n, and handling requirementsof epoxy resin-systems when applied oand uyed with concrete and mt~rtar. asie.,oresented. Thei adhesiveness' of e-pox4 and i.

hmcl thirmal, :and physical prop-rties are givehn The-mbdificatibn of the foib-going'properties to accommodate given situatlbns.is reviewed.

.Problemse encountered in csirfaeeprepa;rctioh r*e reviewed aiid proce-dures and techniques given to insure successful bonding of ihe epoxy to the other, materiialS Temperatue: conditioningzof the base material and'epoxy compound are outlined. The, cleaning and maintining of equipment isre-viewed. Procedures to be follbwedin theoapplication of epoxy compounds in the seveirl use situatiohs are given. Th*' n*pqtdht faciors which insure that the epoxy compound will harden (cure) and therefore perform Its func-'

tion are disc ussed to'.gethir wi~th a'aidn~.e of the hardeninglrate.Tke aoilr-

genic and toxic nature 0ofepoxies and the chemicals used with)'them in the indusor create a 'hcard and porecautions wvd taied roughout,th Ie repo..

Keywords: abraslon reststant coatligs; abiasive blstliig 'acid treatrnt (oon-aete), adhesion* adhesives: 'ggregates; bonding; bridge des,,; chemical analysts; chemieýal ta~ck;,

dieaiin-h coatinigis: cornpresw.a~it;cnrt concrete finishes (hirdened 6onoete); concrete pavemnents; concretes,

caecking, (rcuig;electýicalpropertie's epoxryresins; Ilsuralstrength; floor.topprigs;,

f1esh c6lcrees; grout; grouting; history; joinits (junctions); mitalSl miX pro-portioning; mnIxidng; mortars (mnateria;. patching;' plastics; polyrners. Ond resins; poputs reak es.acing; shrinkage; skid resislanc; stairwaya;ý temperature;,

tensile stf-eng'h:underwater oinstfnctlofi; *vatrproocf6oaiting; wood.

CONTENTS.

Chapter'1 -- I ntroduction, pg.- 503R1-21

!., -- Bac.kground I,2 -- General 1.3 -

ScO Chapter 2'- History of epoxies,.pg. 503R-4 2.1 -- Origin of epoxies 2.2 --

Early attempts at using,: epcx~ses 2.3, -- Development of epoxy 'applications 2.4 -

Present: sttus, of epoxies ACI. Cmmittee Reports, Guides, Standard Practices, and Commentaries are intended for guidan6ce in designiing, plan-ning, executing, or inspecting construction and iri preparing specifications. References to these documents shall not be made in the, Project. D:ocnuenis. if'items foun d in-these documents,are dtsited -t be a part of the Project Docu-ments,, they-should be phrased in mandatory, language and incorporated into the-Project,.Documents.

with concrete ACI503R-93 supersedes ACI 503R489 and beameeffecwve July 1, 1993 copyright 0 1 93,.American Concrete Institute:

AIMrihts reserved including rights of reproduction and use in any form or by any me

, inluding thekg of6 copies.by.a~ny' phot, pc, o by any eec.

ironic or riechanical devices, prifitedoi Wfittenor oral,*rrecoidmng for ýund or. visual reproduction or for use in any knowledge or'retrieval system or device, unless permissionainnwrItng is.obtamned fromrihe copynrght proprietors.

503R-1

Section Z03 503R EC 75219 Page 2 of 28 Chapter 3 -- Chemical and, physical characteristics of, ep~oxy, resins, pg. 0, -

3. 1-General',

3I. -" Adhesion properties 3'.3 -- Stuscptibi~ity ýto hemical attack

3. b-Eectriica'l prope irties, 315 ;-'. *b*raesistance

• .3.6 -- Re'siliencte

,3.8 -- hermalexpansion.

• ,3.9 -- Exothermie reactiqn dluring.cur~e 3.1~0-

,.CurYigand aging stresses 31--Termosettng properties Chapter 4 -,Uses Of ep"oxy r).es.inisiý, p.503R48 4.1 % I General 4.2 -- Potectiye coating 4.3 - Decprative, coati.ng

.4 -- ' Skid-re~s~stant, coating 4.5

'- Grout 4.6:-- Adhesive, 4.7 7-Binder for,,epoxy mortar or.concrete 4.8,--UnderWdater. 'applicati6rn 4.9.

Epoxy modifid econcefe; Chapter 5 - Preparingsurfaces for epoxy compound aipplication, 'pg. 50394-1I 5,1

-t Geijeal 5.2!7, Concfeete surface-evaluatioin 5.3 -- RemiVal 6f6concreftefor'iepaits

.5.4 --'Surfface' preP,*ation 5,.5.. Temperature conditioning Chapter 6 - Preparng' epoxy compound and epoxy mix-tures for use, pg. 503RT13:

C"k6.1-Geel 6.2, - Temperature conditioning, fmatdiial 6.3 -- Mixing aNd pr,-po ionihig-6.5-Cleaning of equipment 6:6. Catation of solveits and strippers Chapter 7 - Applying epoxy comp"ounds, pg. 503R-16, 7.1G-- G eraldconsiderati6i*o*

72-Specific appjeliatior 71 Ufide wter applicatio' Chapter 8 - Hardening, pg.. 503R-3I 8.1i -- Rate of ~hardeieng*:

,8.2 -- Adjuzsting the ihardlening rate 8,3, Opening&thejobto service Chapter.9-Handling precautions, pg. 503R124 9.1 -- General hazards.

9.2.. Safe handling 3 Whatt~o 'do in case of'directicontact

.9,.4 _-Use'of solvents 9.5.-- Education of personhel1 Appendix A " Test methods, pg.ý 5031-25 A. I,- Field test for surface Sloundness:andl adhesion A.2 -- Simplified fiiled tst loiufaed unns Appendix B -

Terminology, pg.ý 53R-28 CATE INTRODUCTION 1.1 -Backgroind 1.1Ai "-*. There aremmay charapteristics,of.epoxies and their uses which maketihem adesi-railea.deivNeifr use,.

wit h con6crete. Some, of tfiese advcan§tagd

,:are.

.1..L1M AdhesIon's-Epoxy tesin*,av Iq excellent a4-heSiy.etquhaities`.ifad Will bond`.tt6,fiteArl all a

nqi stoiin:

materials. A few of-the tnonpolar termoplastics su.h!,as polethylene, present adhesion problemis, andý are excep-tfions.

1.1..!2 Versatiity h

- T'he widoerange of -available' physical :and';hemical :properties,,of epoxy resin systenis makes, their c6nsideratioi

.i'site in ainy sition in-

olving 'repair; "o'ver'rlayi

gcoating, rf adverse' envirbnment, of-concrete. The variey of curing agents,, extnders, dilu-ents,.fillers *iot,,her -modifiers avai abl e

lator permit theattainment of special.characteristics for any-,' arcular applicatiodt.

.1.3" Che6niiIl resistince,--Epoxies ae resistant

'to"the attack'of acids, oils' alkIalies; arid s6lvents.:

1,.1.1.4,Low shrihkage-- C.ompared p o0ther.thIear-

,mosn ting,resins% epoxies;have lw'autogenwos,,sh inage.ý Formulations ýare available in which, eýffeci,

.inrear shrinkageis as,low as 0.001 percent...

11.L1.5 Rapid *harden)ing,- At normal ambienttemn-

pei atures' it'i~s pssibfe :for a mixed r6sin ind 'airdener Isystemto go froma' liquid to, a 'solid *stAte in a iatter"6f

,several minutes, of the time can be-extnded s'ev~eri hoursby chaniging

_, 'system.

S.116 Moisture, res~istance -- A thin coating of'an appropriate,epoxy system,can 'provide a,:,high degree of impermeabhiity even Twhen' continuously ifunidated in'.

water. Some, though not-'all, epoxy- 'm" atenrials absorb sig-nificant amounts.',of water in ýa mi~it-enivirnmefit.; Selectl and use epoxy p0roducts (a4hesi'ves, xp~atings, moars) that. have,. low water absorption Waiter' aSorption will not be a problem <if'tie~material hias, less thian"1 percent' absorption asmeasured by :ASTM-D 570,and'specified'b ASTM C 881, 1.;1.2 -

• he-,benefit, of',using.epoxy: resiins are oiote-Worthy buitcaution mustalsobe *exerdised. Tefo"llwing discussibribriefly ýsimmri zes' '>ome of the'. preOcitions.

necessary.

1

.1'i.2.,

strain compatib~ility 1.1211 Eox bnds-eyraidlyto a concrete surface and. within a *shOrt time may be considered as' monolithic..'The,autogenous.shri'nage. strains.,whidh take.

place i.ir;some epoxy foriulatins' during curinig !can; cauise.

severe strains at the bond line and when combined wit thermal. stiArais contri~bute signi ficýantly to ýdelam"ination,

Section Z03 EC 75219 EPOXY COMPOUNDS Page 3 of 28 503R-,S generally by failure.,in the top;: 1/in: (6'mm) of concrete.

interface.

1.1;2.1.2 There is.a wide differencein the coef-ficients of thermal. expansion between concrete and the cured epoxy. Even normal :temperature variations can be the cause of delamiinationi. Filling the "epoxy system with

,fillers' such, as silica, reduces the difference in thermal expansion in proportion to'the, amount used. The use. of

,a flexible epoxy conpound Will allow the esystem to adjust

ýfor the, differenc in 'thermal coefficient of expanion.

1.1,.2.2 Theriosetting plastic -The component s Whidch: fake up the epoxy ýystemr must be mixed thor-oughly and close. control of temerature rmust be :exer-cised before and.duriinmiing

g. Selection of the epoxy formu~lation that-will cure ata given substrate temperature is crucial to the. cure. All epoxies will not cure on cold: substrates. Proper selection -is the best solution. ASTM C 881 specifies three temperature cure.

classes, Once curedAthe epoxy Will not melt. However, many systems lose sorne of theii :elasticity at.higher temperatures and become cheesy since their mechanical properties chage iicAn*ly bdyond 'theirheat deflec-tipon temperaturen

_(T).-fhe HbT -is different for each formulation but for those systems: used in construction,.

itr generally ranges from 60t6.160. F (151tb-71 C).

1.,2.3'Slabs on grade -- Slabs on. grade can pre-sent, unique bonding ptoblems if there. is moisture present in or under the slab duri'ing;applic'ation and cure of an epoxy (or any oitier imperviIu lymer) maierialt on the slab.. Rising moisture in the slab caused by capillary action canh.exert forces on ithe..epoxy-material that will prevent an adequatebond from being achieved.

Even 'if moisture is not present during application, and cure these same forcescan ;subsequently cause loss of'a bond that was' weak because of other factors such as, inadequate sUrface,.prepaation; 112.4 Safety -'Epoxy compounds areq allergenic.

and safe handling practices¢ must. be exercised in each instance. Solvents used, on fthe job to. clean epoxied equipment oftea, require fihbre, caution than the epoxy.

Previous 'expeririice di'ctates that the,user be thoroughly

-familiar with the' informationf tontained 'in Chapter 9, Handling Precautiois.

1.13 -- The foregoing captionscanbe satisfied by using the appropriate. epdxy. system -selected on the:basis of a careftilly prepared listing, and eyaluation of all job and application restrictions (ihose,*which bear'on handling are noted in Chapter' 9) and requirements 'involved. Epoxies' have very selective'properties and it, is unwise to. rely on a general specification or general performance crit1eria.

1.2 -, General 1.2.1 Recommended"references -The documents of the various standardsproducing organizations referredjto.

in this document'ar 1listed, belowwith their serial' desig-nation.

,224, R Causes, Evaluation, and.Repair 'Of: Cracks 'in Concrete ' Structures 503.1 Standard Specification for Bonding: 'Hardened Concrete, ýSteel, Wood, 'Bck, anid Other Mater-ials to Hardened Concrete-with a Multi-Com-ponet Epoxy Adhesive,

'503.2 Standard Specificationi for Bonding: Plastic Concrete to, Hardened 'Concrete With a,Multi,-

Component Epoxy Adhesive

503.3 Standard Specification for Producing aý Skid-Resistan.t SIface o 'iConcrete by the Use, ofa Multi-Component Epoxy Sytem 503.4 Standad Specification R'for Repairing Concrete with Epoxy. Mortars 504R Guide to Joint. Sealants :for Concrete Structures 515.1R A Guide to the Use of Waterproofing; Damp-pr6ofingi Protective, and DecoratiVe Barrier Systes for.Concrete ASTo C88 1 Specification for Eopxy-ýResin-gase.: Bonding Systems for-Concrete.

C884 Te*st-Method for Thermal,Compatibility Be-tweeh Concrete and, an, Epo#y-Resin Overlay D: 570 'Test Method for Water Abssorption of Plastics D'648 Test Method for Deflection Temperature of Plastics Under. Flexible Load (1882ý0 Pa1264 psi)

ANSI Z 129.0 Precautionary Labelingof Hazardous.Industrial Chemicals K168.1 Guide for. Classifying anid Labeling Epoxy Pro-

'ducts According to their. HaZardous Potential-ities Code of Federal 'Regulations 16.WCFR 1,500 Hazardous Substances: and Aricles;.,Ad-.

ministration and Enforcement. Regulations

,29 CFR '1910 Occupational Safety and Health:Standards 49 CFR Transportation',

The preceding publications may 'be obtained from the following organizations:.

American-Concrete Institute PRO. Box, 191,50' eroit, MI 48219-0150 0i16 Race Street Philadelphia, PA '19103 American National Standards, Inc.

1430 Broadway New York, NY '10018 American Cohcrete Institute.

Section Z03 503R-4 EC 75219

• ACI COMMITTEE REPORT Page 4 of 28 U.S. Office of the Federal Register National, Archives and Records Administfation Washington, D.. C. -20408

1. 2.2 -- This report is based on those known and most accepted -field practices for the use:of epoxy resins with concrete. It provides the user with an adequate guide for successful. application-and performance. of epoxy resins, to the extent of its coverage. However, the epoxy supplier, should always be consulted cdicernihg each hew variable introduced.by the user' 1.3 - Scope

.13.1. -- The rapid growth of the use: of epoxy com-pound in the concrete indu stry and the, proliferation: of available epoxy systems emphasizes the need 'of this com-mittee report.'The wide range. of epoxies which can be used as adhesiVes on, in, or With concrete limitsthe detail which can be-given herein'.

The result is 'n oft6n brief, coverage of ay paticua topic with constant referral of the, user to the formulator for.de tails of application, and performance. Nevertheless, those problemsi'S: Which-are geneally enicoumtered in the'use of epoxies with concrete are. noted and their ;solutions presented.

1

-3.2 Ephiasis is giyen to the praration of sur-faces to receive epoxy adhesive', details of compound pre-paration, use and -aýpplication,, with notesconcerming rate ofhardening, of compound, and cautions to be exercised when using any.epoxy.,Ranges of physical properties are noted as: well as possible uses of the. material.

C4HAPTER2 - HISTORYOF EPOXIES 2.! -1 Origin of epoxies 2-4.1 General-The word "epoxy" is of Greek-deriva-.

tion. The Greek word "epi,." which means "on the outside of," was combined With theý Word "oxygen" which de-scribes the presence,-of the oxygen, atom in the molecular structure. In short, the word is a Greek description of the chemical symbol for the family Of epoxies (see Fig. 2. 1).

2.1.2 Discovery of epoxy applications -- The first prac-tical application of epoxy resin took place in Germany and Switzerland in the 1930s with concurrent experiments being conducted in,.the United States, although the :basic chemistiy had been knoWn 'for sevetal decades. Thie flist known patefiton epoxy was issued to Dr. PierreCastan in Switzerland, in 1936. Three years later, Dr. S.O Greenlee ofthe: United States explored and developedý several basic epqxy systems, many of whiih we use today as adhesives and.,coatings.

2.2 - Early attempts at using epoxies 212.1 Generali-- Limited piOduction of epoxy resins started in the.late. 1 9Os and commercially produced poy resin adhesive became available in the early i950s. Initial labmorory tests using eppxies on.concrete also 'began in hep latea 1940s and were directed toward Fig. 2.1 -- Chemical symbol for the familypof epoxies their use. as coatings on floors and' highways. Develop-ments, were limited to-the laboratory until about 1953, as engineers and scientists: attempted to :identify the: basic' physical properties and probe potenial t!usesI f epoxy systems.

2.121 Early fieldtes&s-for bonding 2.2'J2.1 First interest in the use, of'.epoxy as an adhesive in the.construction industry was-in 1948 when it was used as a bond for two pieces of hardened concrete.,

Epoxy proved-to be a. satisfactory structural :;adhesive with the capability of being stronger than the concrete. it' bonded together.

• 2

!J2.2'In 1954 the Califo ia Highway Departnent, became interested, in, epoxies. as' a bonding agent for raised tffic ine markers:.on,concrete highways. The suc-cessful utilization of an epoxy asý a bonding agent encour-aged the extension of'research into the field of structural repair. of concretej and the eventual application ofd an epoxy-po1ysulfide 1olymier, as a bonding material for join-ing niew 'concrete to: old.

2*2l23.Early field tests for, surfacing materials. -, In 1953 the Sh ellChemical Corp. initiated Bfield tests to evaluate epoxy systems as surfacing materials on highways, follow-irg, successful laboratory tests by the company. Favorable results encouraged the'pu*suit ofthis'as a solution to an age-old,'problem of restoration of deteriorated coincrete surfaces.

2.3 - Development: of epoxyapplications with concrete

";2.3.1 General -; Epoxy formulations developed until there'were available systems withla comibiriationmbf pro-perties which "made, them, unii'quely suited for usedas an, adhesive with concrete. They had high bond strength, characteristics similar to other structural materialsjwhen cured -and long-terh resistance to. aggressive environ-m ents, with easy application characteristics, and low-shrinkage during cure..These properties led to-many dif-ferent*applications, some of which are discussed 'below.

1..3.2 Epoxy for bo7nding -- Theý ability of epoxy to

Section Z03 EC 75219 EPOXY COMPOUNDS Page 5 of 28 503R4 bond!. iwo piecesý of concrete generated interest in the possibility of bonding f-resh onCrete 'to existing concrete.

Experiments' with the latter situation,met with limited success until the development of, epoxy 'reSin-pOlysulfide systems. Sirice that time' efforts with these and other recently developed adhesive systerms have 'ektended their desirable.'properties. and 'their-general acceptance by the concrete, industry until they are-now widely used.

-- _. Epoxy for grodiing 2.3.3.11Epoxy injectionsystems --,Epoxy, injection as a ameans of performing,,strucii.al. grouting 'and repair was first, used inthe late 1950s, The approach wasto premix the epoxy ani then pump the mixed epoxy-system. The injection of epobxy intostructthral cracks pe*ritted for the

.first time a positive technique for the restoration of the structural integrity of cracked concrete. In. 1960'a system

-was developed utilizing pressure iijection with a mixing

'head at the nozzle of the injection gun' which expanded theapplications of epoxy as:a grouting'adhesive in struc-tural-cioncrete.

2.3.32 Epoxy bolt, grbut. - The, use of epoxy as a grIout to. bond bolts or dowels'.to hardened concrete was first attempted in the late 1950s. Tiis application,.'came about from-the need to,grout, bolts in existing concrete, slabs for mounting heavy machinery, Concurrently, epoxy grout w* ued tobond.doweis into 'the ends, of:existing concrete slabs as a shear'transfer'mechanism for exten-sion of existing-slabs, The use of an epoxy grout'which' could attain high,,

early strieng*,hand *hicih would not isIhnk sig ificantly during curing solved an old-problem for manufacturing, plants, ihat, of rapid installationof.new equipment, with minimum delay until. full] operation:

Epoxy grout' has also; been successfully usedtfor instal-lation of handrails, architectural metals, precast concrete panels, structural 'members (both coricrete and steel),

concrete railroad ties, and for numerous other applica-tions.

213.4 Epoxy :coating materials.

2.3.4.1 Epoxy seal coat 2.3.4.1.1 Epoxy sealcoating was first applied as test patches: in industrial plants along the eastern coast in 1953 and on highways. in 1954. Although there Were vary-ing degrees of success'anid failure with these applications, the 'initial results :were, encouraging to, many observers.

Large scale experimenta! applications were attempted in.

1.956 on '-the Wilbur' Cross, Parkway, the TiiboroughL Bridge and the. George WashihigtonBridge. The apparent:

suc'cess of.these latter.-applicatidns, led'to orte.elaborate testing all. across the United States 'by 1958. Tests at that time Were conducted primarily with.coal tar epoxies ap.

plied.,s. sseal coats and then given a skid'resistant surface:

by broadc.asting.fine sand or emery aggregate across the surface., This procedure, while successful in, many re-spects, was not" as utopian Aas had been hoped. Then in 1962 a thin topping. of Asphaltic concrete'on top of a coal tar epoxy seal coat was tried-as analternative solution on

a. bridge in New York City Which moved, quite:successfiut.

The method. has since been extended, using other'epoxy systems.,

23.4.1.2 S*al coats Usingepoxies"of low viscrSity' have also been successfully applied', on highway, industfiil and cbofimercial stirfaces.

2.3.4.2 Epoxy polymer concrete as a wearing course

-- Epoxy polymer concrete wa firt-used as a wearng course in. the repai'.of popouts 'and,spalled areas on the surfaces of various concrietebridge-decksin:California in 14957, on the San Francisco-O kland Bay Bridge, 'and in industrial plants, 'and' warehouses. The-, epoxy 'polymer concrete. consisted primariyý off the epoxy resin system and clea6, dr.ywell-graded sand By. 1963,1'eVeral bridges in various parts of the United States had been success-fully resurfaced With-epoxy polymer concrete.,

2.2.4.3 Epoxy resin specificdtions -- The' U.S. Army, Corps of Engineers published the first Federal specifica-tion for an.epoxy resin system'in 1959 and ASTM specifi-cation C 881 was first' published in 1978. The-use of the epoxy. systems has since expanded, in many directions, be-cause of requirements f6r 'soluti6n o'f coating, patching and resurfacing problems.

2.4 -- Present status of epoxies 124.1 Epoxies. are presenily, used with,concrete in the, form.of catings;. repair 'materials grouts, bonding agentsi paints,.adhesives, epoxy mor and polymer cc6riCrete, segai coats, penetiating seale"rs wearin, g.surfaces,..and as, admixtures' to portland cement concrete*to make 'epoxy polymer modified concrete. Thus, the appeal for epoxies has beenenhanced, both from an, economy and perfor-mance' standpoint.

CHAPTER 3 - CHEMICAL AND PHYSICAL CHARACTERISTICS OF EPOXY RESINS 3.1 - General Epoxy compounds are generally formulated.in' two or more parts,. Part A is most often Sthe portion contaihing the epoxy 'resin and Part B is its hardener system. Almost without exception, epoxy s'ystems must be formulated to make 'them Siuitabie for specific end uses:

3.2 -

Adhesion-properies 3.2. General ý- Epoxies bond well (Fig. 3.1) to al-

mosteverymaterial'providing that an appropriate surface preparation has' beenfi, given (seeG

-Chapter 5)., Because' the quality'and surfa cconodition ofconcerete is rarely.comn-pletely known; tests for adhesion are avised (see Appen-dix A). Ther are mny reasons why epoxies make good-

.Adhesives including, but not limited to, the, following:

a) They can be in-liquid, form ýand yet. contain no volatile 'solvent b) They adhere to niost.materials, used.inconstruction.

c) No by-products 'are generated dur-ing curing d) Cýuiing shrinkage-ig, 1w

Section Z03

'5031R4 EC 75219 46 COMIMITEE

'RIEPOT Page 6 of 28 Fig. 3I - Epoxy adhesive when,.properit'iapplied canform a bondwith: greater srength than the concree o O:,which lit is applledl as shoawn:'h&ere,(courtesy L. kitdie, Consýultig.

toxiC.

S3.3 Suscepfibility to chemical attacik 3.. -Epoxies are, consideredma generallyf-resistant to, chemical attack. A general comparison wihi.oncrete is gven i, fT lalle-30.2 Table3.2,- Chemical properties of iepoxy and conicrete Wet-dr cycfi'g

'Excellent Excellent:

chl~dede~in satsExcelen Fair Muriatic acid.(15 percent HCI) 8'6e:lt"ý Poor Foodsý 'iacids (dilute).

'Good, Poor sugar solutio'ns" Excellent Fair Gasoiune.

Exceilent Excellent Detergent' cleahing solutis Excellent

'Excellent Alk alies Excellent Good

,Sulfates Excellent Fair

'Epoky systems uised'to.,protect concrete from the& ef-fecnd food spillage must,,be rompounded for specific u6tl~iesl.ý for example, 'a. 'syse eitstt tcai m*ay,not be,,rsistat~to all toicentrations of aetic-acid.

This isecause many org Ianic acids 'hav vprpessures lower, than water-and, therefore, as8 spillage evapoiraes,

,the acid solutiion becomes more:.conentrated. Another

,note, if caution relative to, poiential.f faiures is that-chemical'.resistane',tests are often ru' at 77.F (25 C)

Whefeks spillage may. bemuch hotter. Fod acid absorp tion by*

e poxy,*- reitions ofproemperature. Aid

,arbsorpi ionel*tai50 F (665 t

Ce may bý4ep wo 100tfimes'the o

epaion'a i

77.17 (25,C). Furthe rer, vegtypie

acid spillage ually contain plant. sugars.which for a series of organicacid when ioodid.-These acids, usually-pre'sent'ninsmall am~ounts,,; also may become more concen,-

(rated as evaporAfion 6Ufspillag 'I oress -Therefore, propeIr seledction of the e60x formnulato iinprAnt to the sues fthe substrate; pr6tection, Follow the r&

commendatos:.oI the epx mnanufacturer. A typical in-sialation is shown in Fig.

2.

e)TLbong time dimesibrial stability-is good

)They aeh~~~sl'n opesv strengts, g) Appropiate -fomiulations are resistant to:the adion pf weaathering, moisture, acids,,alauisand,mosthotheren-Vironmental' factors.

13;2.2 Mechanical :protperly comparisons 6f epoxies. and conicrete

. 2..

21 Physcablproperties -In Table.3.1 epox;

-streng*hs; nd tensi ielongation are, he vahies at.Iime. of mpture: However, even highly elongating epoxy,'binders Vmay have negligile sire*t*h when eaeilj,filled.'

Tablie 3.1 - Corparative iechalifical propeities,of. epoxy system and-66c'crete:

Flexural' Th6sile Comnpiessive Tensile strength strength sliength elongation Psi'(MP.,a)

-ps (MPa) psi (MPa) percnt:

Str1Jctiral 500-40G10

.300.700

3000-10;000

' 001'

.concrete (3*44:9)0 (0.148)

(20.768.9)

Epoxy 0500-5000 500-7000 0

0-i2;000 O.2.to 150:

compounds (10.3-34.1)

(3.ý4-:9)'

"(3,442.7)

(typical)

J3.2.i22Temperature effects' - E'poxy resins ýreact upon: combination to forna thermosetting plastic which thereafter dOesrnot melt. The.properties of:a:'cured. epoxy system' generally thn'ge Vei:littleý.With tempetatiresWelil 6beW theý Heat Deflection Temperature (HDT). as% mfeas-ured bvy AS

)

D 648 1 B e ginn ing ifite region -abou-t i8 F'(10 C), :below tie HbTrigiadty,; creep resistance and chemicalresistance :are averse*y*

efecte as temperature, is increased. Above 572 F (300 C) most resins will char, and &generally volatilize..Thed.'resuting. fumes may :be, Ji.

32 -Epoxy; mortar floor toppf ing'i a food, proc( ssing.

'planht(couts P rotec Inustries)

Section Z03 EC 75219 EPOXY COMPOUNDS Page 7 of 28 503R-7

.b 313.2 - Epoxies are widely used.for industrial applica-.

tions where,:chemical spillages.'are the, normal environ-mental condition, Consult With the.epoxy' manUfacturer to determine. which formula should be corsidered.

3.4..... Electrical propertieS 3.4.1 - Epoxies are excellentelectrical insulators.

3.4.12 -- Special techniques, mustbe employedjto enable an epoxy, formulation to be a conductor.or partial con,*:

ductor of electricity. There are places. where this is necessary, such as operating room floor surfacings in hospitals, clean rooms andrnanufacturing areas where static dischArge 'cannot be tolerated. Th6 reader is re-ferred to the instructions from manufacturers specializing in such appiications.

3.5. -- Abrasion resistance 3.5.1 -- Epoxies~can be formulated to withstand severe abrasion, buttconditions of use. have to be understood be.-

fore the. best selection of materials can be made. For example,, will the surface be dry or wet? WHt or cold?

Will abrasion be from rubber wheels,, steel wheels, water-borne, rocks, etc.? For, specifi.c end uses,. the epoxy com-pound manufacturer, should be consulted and&given a full

-description, of'ervice environmental conditiofis,.

36 - Resilience 13.6.1 -, Epoxies: can undergo deformbation", and yet.tre-covet; and returni to their original, shape providing that.

their. elastic lirfiit' has not been exceeded.

137 - Creep The amount of creep' which. will occur depends not

.only on theJoadbut also on how close the setvice-tem-perature is,to the Heat Deflection, Temperature (HDT),

theý amount; of inorganic filler in 'the: system, and' the' degree of confinerneft of the epoxy, system as it is l*aded.

3*.8

-Thernal.expansion 3.8.1 -- A major difference between epoky: compounds and. concrete lies-in theirt coefficients of therimal expansion (see Fig; 316).

.182 -- Steel and concrete usually have similar:thermal expansions. Combined as reinforced concrete, the differ-ence. in their coefficients of thermal exparsion does. not usually become, a problem either in design. or-use, On, the pother hand the :considerable,difference in coefficient of thermal expansion between epoxies and portland cement.

concrete does require careful consideration,

':3'8.3 --. Consider -the factors indicated in Fig. 31'3 where, (a) i§ a slab of concrete'.surfaced with an epoxy (b), Due

'to the difference in coefficients of thermal expansion as the temperatmre., rises,(b) will attitmpt to grow larger than (a) and, if the concrete -were' as elastic as theepoxy, the result would be-as 'shown in Fig. 3.4, 6bviotisly ekag-gerated. Conversely, if the temperature drops; '(b) Will shrink 'more than,(a).and "will produce the A.defm'nation

,xx-ff 11 a

Fig. 3.3 -- A layer. of'epoxy (- adheredto a thiclness. of concrete (a) b Fig 3.4 - The ebect of temperature'ihncrease, inan 'dpoxy-concrete system a

Fig. 3.5-- Effect of terperaturedecrease, in an epoxy-concrete sstem 7;

E qu 42-36-30-24-Is-

,coftrele~

'I -'

I I

T n*U i

2 3

4 5

6 7

A~egiti-bintder rii;P e

9 1o Fig. 3.6-The effect of changes in' the sand aggregate-binder ratio on the thermal coefficieit of ani epoxy system shown.in Fig.3.15..

3.8.4 *-The higher.elastic modulus of concrete tends to.

restrain, the movement' of the epoxy, thereby causing se-vere stresses at the interface upon' temperature ch'anges.

Epoxies.. yield understress,,ind, 4if properly 'formulated.

they will accomnmodate relativ.ely larger dimensional changes resulting from-thermal.,effects. Also, the coef-.

ficieht of.thermial expansion,of the epoxy c.,Iani be reduced by the addition of fillers, see Fig. 3.6, with an, increase in modulus of elasticity.typically resulting.

3.8.5 Thermdl eoefifient. of epOxy-daggregdte.systems --

The thermal :coeficient' of anm epo:x system will be reduced As,. the aggregate c'ontent of the systm is in'-,

'creased. as iNicdted in TFig. 3.6.

Section Z03 EC 75219 ACI COMMITTEE REPORT Page 8 of 28 503R-8 Fig. '4. ) -- Application of a thin epoxy mortar floor couzing in an area subjeci to abrasion and chemical attack (cour-tesy. Sika Chemical,Corp.)

di

-p Fig. 4.3' - Epox groutinig of kiywqys inrapid transit bridge (courtesy 'Adhesives Engineerihg).

and applidation0 to add the: maximim quantity of aggre-gate.cnsistent'.,with the intended application, or both.

3.160 - Curing and aging. stresses.

Curi'ng and aging. stresses are developed in epoxies.

These streses can. bei minimized by correct formulaiion.

3.11

- Tiei-mosetting propertfes Epoxy resins are therrio setting plastics,. i e., in the process of hardening, they undergo chemical change and cannot be: reliquified~by heating.

CHAPTER 4 - ijSESOF EPOXY, RESINs 4.1 -"General Epoxy.:resins, meetihg.ASTM C 881 have good adhet-ence to concrete under all conditions whether wet or dry, and have been found useful for a wide variety of applica-tions w:vith concrte` (Fig. 4.1-.4,5). For the best perfor-malice under each.,condition of iiuse, the propertiesof-the epoxy resins ystem. should be tailored to m6e6t thle'spcifi needs ofteach type of applicati6n. Thus, it is? uhlikely that q system consisting, onlyi of an epoxy resin and. piue had-ening agenitwill find wide'utilif I.jt is for this reason that the. epoxy resin, systems sold c6 mmercially are genrerally the. products offormulators Who specialize if frodifying the, system :,with flexibilizers; :e'k-enders, dilfientsi, and fillers 'to' nieet Specificend-uei.:reqtiiremeiitS. It logictll!'.

follows hati.iis important to adhere.to the formulator's fecoimendations for use.

Fig. 4.2-- Afi epoxy sealer and light reflector on th'e :walls of a highway tunnel (courtesy Adhesives Engineering) 3.9 -Exothermic reaction during cure

,EPoxies-develop heat duningtheir~ctire.e Th-e,temipr-.

ature rise will depend on mass as welldas formulati6h. To keep: this.temperatrterised t aminimum, it is-advisable:

to maintain a highý surface area to volume during,mixing

Section Z03 EC 75219 Page 9 of 28 EPOXY COMPOUNDS 503R-9 Fig. 4.4 - Repair of a conicreie bridge railing, uprghi ?courlesy ProSexy Idusfies) 44.2 - Protective. coating 4.2.1 -- Because of.their impermeability to water and their. resistance to attack by most acids, alkalisiand many Solvents, epoxy resin systems have' been widely used as protective coatings for concrete.. Such coatings may-vary

• , om sealers with th.in. films of2,or 3 mi mm) thickness to high-build coatings amounting to over-J lays. When used as a coating it, is essential that the sys-S.tem.

be compounded. so as to. avoid or. relieve excessive p.J..

,7' "*i shrinkage.and thermal stresses between the. coating and V-7-C concrete surface'.in ord erto prevent delaination of'the V..

coating. through loss of bond or failuie oftthe concrete.,

4.2.2 -- "Same.of the most severeenyironments for the:

proiective-coating t'pe. of appliations are those,,of the highway bridge deck, industrial floor and, parking. deck surface for the purposeoof preventingpenettration oftacid

,KA fY:rain, chemicals, waterand deicing solutions into the con-

.crete. he coating may be.used.eitheras the we g Sur-face itself or may be covered by, somei type of asphaltic concrete overlay. In either case 'the: coating should'have

.mineral particles imbedded. in the surface to" provide ade-quate skid resistance., for traffic When. it is used as the wearing surface (see Section 4A), and to provide bond when used beneath a -bituminous, 6Verlay.

4.2.3 -- Many. industrial environments involve exposure of concrete to acid, alkali,, or. solvents. Floors and: walls located in such areas-as well as Storage vat, can be

.. made chemically r.sisantby the use.of the epoxy resins.

4.3 - Decorative coating Epoxy resins serve exceptionally well as tile-like Fig. 4.5-.Repair of a column-base, connection All! exposed coatings*.howeer,. ithey surface chalk in.,outdoor 'expo-lsurfaces Will he epoxy coaled prior, to casting new concrete sure.I te case6: of wall surfaces, epoxycoatingspresent.

(courtesy ;Protex Industries) ahard, glossy surfacý6and -can withsadfstheaibrasive and.

Section Z03 603RW10 EC 75219 ACI COMMITTEE REPORT Page 10 of 28 coft6bsive action of deaning materials. Epoxy coatings.areý especiallysuitable for floors, ca, washing areas, and. §uch outdoor locations as pafios-and porches,. because.'oftheir good resistance to wear 'and moisture. In this conne.tion, they make, an appropriate coating for swimming pools, serving the additional fi~hction-:of sealing the c&bncrete',

surface to the passage of water.

4.4 -- Skid-resistant.oating.

Concrete surfaces.can be made highly:.skid resistant byý the application of a'n* epoxy coating into r

which mineral particles are embedded. Typical:appiicba.tions are treads of stairways, walkways in certain, critical areas, and high-way pavemnent surfaces near toll' booths. As mentioned in Section 4.2.2, bridge'decks'are often,:given such a skid-resistant coating although the primary'purpose for the treatment is often protection of'the bridge deck itself.

4.5 -- Grout Epoxy resins fimd wide application as grouting mater-ials,. 'The filing of cracks, e'04her 'to, seal -them from the entrance of moisture or to restore the integrity of a struc-tural member-is onbe.,of the, more, frequent :applications.:

Cracks :of 1/4, ih. (6 mn) or less &e*'most'effedti-ely filled with a pourable or pumPable epoxy compound,p'whereas an epoxy resin mortar should be used for Wider cracks.

Epoxy resins are useful as grouts, f6r setting machine base plates, and for groutng, metal dowels, bolts, and posts: into position. in concrete.

4.6. - Adhesive.

4.6.1 -- EpoXy resin is a good adhesive for most mater-ials used in construction, such as 46onretei masonry units, wood, glass, and' metals., However, many plastics, such as polyethylene, cannot be effectivey bonded. Typical apt plications, where epoxy resinhas been used 'for.ementing various materialsto harden concrete ýare. the'joining of masonry units,, precast bconcrete bridge deck gitders, wood and.metal signs, plastic traffic' marker buttons, and the setting of dowels in "preformed or drilled hobles in concreie.

4.6.2 - Epoxy resin is useful as the bonding medium between fresh and hardened concrete for such purposes as bonding a concrete overlay toan existing slab. For this purpose, it -is essential that 'a formulation be used which will cure and bond properly under"the moist' conditions present in fresh concrete. Epoxy compounds can also be used as shear connectors' for composite construction such as a metal beam, and cast-in-place concrete slab.

4.7

- Binder,for epoxy mortar or' concrete' Epoxy can be used as the s,:sole;.binding,material.to form a resin miortar.or polymfier.concrete. Such. mixtures have been Widely used f& patching' or repairing sdrfaCe defects oif many types of conctete structures, particularly highway bridges and:pavements. Epoxy mortars' ard con cretes are also especially adapted to repair of hydraulic stru.tures where continued -submersion lessen' the prob-

-lenmsý of therinal expansion..

4.8-'Underwater application Epoxy resi',formulations a.re.now available:,which, can be used& to coat, :overlay, patch :or grout concrete and

.other construction' materials in the, splash, zone. or under-water, inl eithe~r brackish,. fresh.or~salt'water enVirOnments.

4.9 "- :Epoxy-modified concrete Most recently, ýepoxy resins when emulsified have found use.as an.additive to portland cement concr6te and mortars to form "epoxy-modified concrete." These, epoxy resin systerns'when added to concrete -can increase adhe÷,

sion.0f the concrete to concrete or to steel, iricreaseý strength, and reduce permeability. This use. of epoxy resin is relatively new,-but is growing.

CHAPTER 5 -

PREPARING SURFACES FOR EPOXY COMPOUND APPLICATION 5.1 General 5.1.4,1-The prepairtion ofsUiffaces to riceivceepoxy' ompound, applications mustbe given c l artention as.

the. boiding capabiity of a prperly sele*c*teepoxy for a

.:given application is primarily dependent on proper. sur-face, preparation. Concrete surfaces to which epoxies are:

to be applied must be newly'ýexposed, clean concrete free of' oose. and' unsound materials. All surfaces, must be imeticulously cleaned :aid be' as dry -as possible, and beat properT surface temperature at the time of epoxy applica-tion. When a 'substrate is still mroist after the, cleaning

.,process, a moisture-isensitive epoxy formula.should'be, used.

5.-1.2.

The method'or combination.of methods em-ployed for' satisfactory surface preparati -on will depend'on' the type, eXtent and location, of the application., If pre-paration' Work involves: the rem6oval 6f'oncriete,:sucfihre-movail-'should be accomplished by' well coitrolled mech-anical means (see 'Section 5.3'.2). Those surfaces. or areas:

which. do not require, concrete removal in depth. must be satisfactorily' cleaned to remove all substances detri mentalito' bond of epoxy compounds. All equipment"for supplying compressed air miasti be equipped With 'fficient oil and:water traps to ;prevenit suace coiitamipnation.

from the compressed air-supply::

5.1.3 -- Prior-to the application.of epoxy resin com-pounds,. itis generally considered necessar' to field test, the condition of the:prepared concretedsUrfa~d to recei've thebepoxy resin as well ýas theadhesioh of tfe'epcxy resin, conmPound. Methods of field surface evaluation, deter-initation of moisture.percolati6n throuigh "the conbrete,.

and 'of surface.prepaation are discussed 'hereinafter.

5.2 - Concrete surface evaluation 5.2.1 General.

5,2.1.1 Effoits'to.btain good adhesioi 'to'a Weak surface are futile since failure of the surface is likely to

Section Z03 EC 75219 EPOXY COMPOUNDS Page 11 of 28 503R-1 occur,. ConVersely, poor bonding can' O'cctr Iith'perfectIy sound surfaces if they are iot properly prepared. Sur-faces should be prepared accordig to Ad specifidcation ACI 503.1, 503.2, 503.31ad 503.4:

a) The, surface must. be sttong, dense andi sound.

b) The surface should be dry:and cleanjie., free.from surface contaminants such asdust, laitance, 6i1 grease, and curing compounds.

c) The surface mhust-be-at. the proper temperature ýto permit Iproper wetting, by the epoxy application -and 'to provide for prompt cu.ring of the epoxy resin compound.

d) Moisture and water vapor may sometimes permeate through the,concrete to the: surface being: treated, arid must be recognized as a potential problem.

Evaluate moisture content or outgasing of the con-crete by determining if moisture will collect at bond lines between old concrete and epoxy adhesive before epoxy has cured. This may be~accomplished by taping h4 x 4 ft (1 X, l:m) polyethylene sheet:to concrete surface. If'mois-ture. collects on underside of polyethylene sheet. before epoxywould cure, then~allow concrete to dry sufficiently

.to prevent the possibility of a moisture. barrier between old, concrete and new epoxy.

512.,1.2 To insure that the.above conditions will, be met, tensile test methods have been the principal means for field testing horizontal concrete surfaces. The same methods can beI adapted for, use, on inclined or vertical surfaces. The tests svrve either of two purposes:

• a) To provide a converient-means. f&t determining the bonding strefigth (adhesion) of'the epoxy comourid to a, siirfate which has been prepared for bonding, or;,

b) To detect a wpikened concrete,surface.

5.2.1.3"The test methods described' in A ppendixA.

are suggested as -being suitable'field tests.

5.2.2* Ev6luation of' surface preparation 5.2..1 Extensive use of'the field test method.

described in Appendix;.A, Section A.1, has shown that where-proper bonding.has been 'obtained on properly prepared portland cement concrete surfaces, -failure usually occursin'the concrete' Such failures"ihdicate:that the bond strength,of the epoxy compound is greater than the tensile strength of poriland cement concr&et and sat-isfractory bonding of the epoxy compound. has.been rde, Monstrated. At the same time, the. magnitude, of stress measured at failure of the concrete indicates whetherthe surface may be weak and requires urther investigation.

An evaluation of the quality, of the. concrete will be required -to properly,evaluate failures, lower than '175 psi, (1.2 MPa), recognizing that in some. instances lower stress levels. might be expeqted and acceptable.

5.2.2.2 The,simplified field test menthod, described in Appendix A, Section A.2,;was0 riginally developed to evaluate, the sufficiency of"surface. preparation for, an epoxy application and to detect relative differences in, Potential surfa~ strength over the area, to be repaired.

This iest method 'is Ialso.considered' adequate to.deect deficiencies in a prepared concrete:surface. A.though ex-perience with the simplified, method' has not been.as ex-tensive as with the field test method (Section.Ail) it is the simpler, less' costly and less time *cohsrinig iest ofi the-two and, therefore, 'has the advantage: of enablirig-more complete coverage. of a ýsurface -area in a given length of time. Average values fom the test method of Section A.2 can be used to assess te adequacy ýof the surface and the magnitude of stress measured ai failure of the concrete indicates whether the concrete is su'f-ficiently sound for the application. -Failure of the port-land cement cohcrete at stress levels be.loW 1,75 psi (1.2 MPa) generally indicates that. the', surface is suspiciously weak and further investigation of the surface may be necessary before full scale application of the epoxy compound.

5.3 ;- Removal of concrete' for repairs 5.3.1. The removal. of the unsound ordamaged cOn-Crete, may be a part of rehabilitation work on sftructures involving epoxy applications (s 'eFig.:

1.), Such 'removal should be accompliShed by well cohitolled' mechanical means.

5.3.2 -- a first step,in most concrete removal opera-tions i tisý generally*' recommendedtat the peiphef of, the 'required removal area: be, saw 'cut to a: depth 'consis-tent with the type of repair. Saw cutting delineates the repair area aand serves. to esefitially (if not. totally) einifminates, edge spalling and. we"esses tat, might.i be introduced by outliiiing the..repair area wit other types of equipmrnit. It also serves t9b pioduce a shoulder.,

against which repair material'can.beplaced and smoothly finished, 'thus producing'a neat appearing repair. The saw.

Fig. 5.1 -- *Removal operation of all unsound concrete in bridge deck down to top steel. Repair was made by bonding.

the:fresh high early strength concrete. patch to :the old

'concrete using an epoxy adhesive :at the interface (courtesy Adhesives Engineering)"

Section Z03

-503R-12.

EC 75219 ACI COMMITTEE REPORT Page 12 of 28 cut line should be located several inches outside of the visual limit: of the defect to ihsure that all, defective concrete is removed and that 'the. ultimate repair is bonded to.sound concrete. The depth.of saw cut should be at least Y,/ in. (13 ram) for 'epoxy-bonded p.rtland cement concrete and'f'moiiar repairs; I/to A iln.(6.tl3 mm) saw cUts:are adequate for repairs employing epoxy mortars providing that removal of concrete within, the repair area, may be accomplished without ispailing or otherwise damagingthe concrete at~the saw ctt 5.3.3 - In.preparing. cutouts for popouts or small spalls wholly within a:structural component (iLe., hot involving joints, edges,, Of comeis), very thin edges (9somtimes re-ferred'to as feather-edging) mniy be permitted, but'tese should be at least -1/4 'in. (6 mm) deep thereby providing a shoulder dfsufficient: depth4 to perm.nit-a smooth inish.

High frequency chipping hammers have been successfully used to make cutoutsifr, this latter.type of repair.

5.3.4 - The concrete within the area delineaiedby the, saw cut must be removed to a depth 'sufficientl'toekpose sound concrete Over. the entire repair iaea: If doubt exists, concerning the completeness of unsound concrete remov-al, it is best to,remove the concrete tQ-what may be a somewhat excessive depth to assure :n..eventuallysound repair. Concrete removal should. be accomplished mech-anically with --medium to lightweight air hammers e.lquip*

ped with appropfiate cutting tools;. or, for relatively large, horizontal areas, othei equipment such. as a mechanical scarif~jng machine may be appropoately ard economi-cally used.

.5.3.5 -

Upon completion of the -concrete removal 9peration, all newly exposed surfaces should be cleaned by an abrasive blasting method. Wh-enwater is used as, the abrasive blasting,'method the wet Concrete; should, be.

allowed to dry (see. 5.211). When' forced drying is necessary, the surface may be dried with radiant heateis, or hot air blowers.

5.4 -* Surface preparation 5.4.1 General.- Proper preparAtiori of any surface to receive an epoxy application 'is of primary importance no matter how carefully other pha.ses 'of the'application pro-cedure have been performed: Bond failure can;.be-expec-ted if surface preparation is inadequate. Proper prepa-ration of a given surface is an art, and a:science and must' be given careful attention.

5.4.2 Concrete surfaCes 5.4.2.1 Recommended procedures' -. Those sufaces or parts of surfaces Which do'not require*removal of con-crete in depth. must nevertheless ýbe piecleaned to re-move all substances detrimental to bond of epoxy corn-pounds, such as laitance, curing membranes,.:.dust, dirt, grease, oils, fatty acids and,:other debris., resulting from

• surface.preparation operations. The cleaning; method or combination of methods: will typically include abrasive blasting techniques such as sandblastiig, Steel shOt

ýbiastirig, high pressure.water blasting 'o*:flam'e blasting.

Whateýer "prepafations, are Used, the r*sulfs0uld-:be 'rat surface abraded ýto an: extent that small-, aggregate. par,-

ticlesare exposed but the surface should not,be polished or be utnnecessarily rough and it must be free Of all sur-face containinafits. Care mustbe exercised to.*ssuie: that

'any water *used in cleaning is. itself clean:addialso -that no contaminants are present: in any compressed air.

5.4.3 Previously coated sufaces --- Surfaces which-have:'

been previously treated with curing membranes, oi!s,,sili=

cones, paints, coatings (including epoxies) and "other treatnients. may be.; encountered. Also, occasionally' a' bond or tack coat-of an epoxy-compound riay hiarden beý-

foIr application 6f'the top" coat can take place, It' is, necessary to completely reiove such material&sdiidc the.

best assurance of complete removal is by abrading met-h ods. When there is doubt concerning selection of 'a cleaning method,, it is considered goodpractice toj make a: small trial ! installation using one or more' cleaning methods, ap'plying. the epoxy cbfi-pound to be used rin the-worki and checking adhesion by, one of. the tensile 'test methods described in Appendix A.

5.4.4 Metal surfaces, 5.4.4.1 General -Metal surfaces must be, cleaned and at the time of epoxy application be free ofdust, dirt, oil, grease, rust, mill scale, weld splatter, and any other contaminant. Abrasive cleaning methods must be carefull-ly considered. Adequate cleaning and surface profile are.

important factors in the abias~ie cleaning selection. The method-selected must be capable of &leaning the entire surface area,.especially when verttical or overhead sur-faces are, to be cleaned,. Predleaning is: necessary-if oil and.grease. deposits are on. the surface. Mineral spirits, naphtha (100 F (38 C) minimum: flash poiht)-toluol (tol-

.uene) and xy,11iare satisfactory solventsftior. ;tis puýse.

Gdod ventilatiori arid adequate safety precautions are necessary When solvenits are used After precleaing and mechanical cleaning,-any dust or debris created by..the mechanical cleaning must'be removed prior to epoxy'ap-.

plication. A cleaned metal surface -isvery susce*tibl* eo corrosion, particularly in, a humid atmosphere, so the Work should be planned to peminit the epoxy'application

-as soon as possible after'cleaning to pretvnt flash rusting, which may occur within minutes.

5.4.42 Test for adequacy of metal surface prepara-tion -- The sufficiency of preparation "of'a metal surface

.can-be-partially determined by use of the water-break-free-test. TheAtest is a check of the suiface tension'of the metal surface. Individual droplets.of distilled Water -are applied tothe surface with anr.eyedropper. Dependingbio the cleanliness of the surface the water Will 'tend `to re-main in a hemispherical shape, or -will immediately spread. If the surface is not clean, the water will not

-spread but, will-behave somewhat.like a drop of water on wax paper or ona -polyvinyil chloride sheet. If the. surface is clean and the surface-tensior is, low"the,water will speaid into a thin film, wetting a, rdlatively larger,area.

There '4r, of course, all degreesý of"Wetting between the two extremes anythig '

than apparent lw surface tension should be sus'ect.

Section Z03 EC 75219 EPOXY COMPOUNDS Page 13 of 28 503R-13 5.4.4.3 Steel.- Epoxy. resins adhere well to steel.

Steel surfaces should'be-abrasive blasted for good results and should be scrubbed thoroughly after abrading, Washed Well, and dried. Solvent precleaning is recessary if oil or grease is Present. Adequate.. adhesion can often be attained using only. solvent cleaning where there is brightmetal.with no mill scale. Surface adequacy should be checked by. the water-break-free test.

5.4.4.4,Galvanized metals.-- The surface treatment for galvanized metals is the same:as that given for steel "except that the surface need not be' abrasive blasted i'n-less there are signs of subsurfa:ce corrosion; The surface

,should be scrubbed thoroughly with a solvent (see Sec-tion 5.4.4.1), washed well with clean water, and dried, A good water-break-free condition should be obtained. Au improved bond can be obtained by etching With muriatic (hydrochloric) acid (20 parts by weight concentrated acid to 80 parts by Weight Water)for 3"or 4 nin. After the etching trfeatment, the surface must be washed with: clean water and dried.

5.4.414.51 Aluminum -- Adequate preparation, of

-aluminum, surfaces is difficult, to achieve and care must, be exercised to see, that cleaning has: truly. been complete.

The NfOllowihg. procedures are designed for field use where, abrasive blasting is not. practical and for large.

surfaceS that cannot be immetsed in.acid storage cyl-

'inders. The aluminum surface must be scrubbed with a nonechloiinated cleaner until a good water-break-free test is obtained and then. etched with proprietary chromate treatment followingmmanufacturer's directions and safety requirements. These treatments are generally plant; operations.

5.4.4.6 Copper and cOpper alloys -- Copper and copper alloys arervery difficult to bond, especially if high adhesive strength is desired, primarily because of rapid oxidation.of the copper surfaces. Abrasive blastingis the preferred method of surface preparation; followed by thorough scrubbing with distilled. water and drying. The.

following procedures 'are recommended asý alternatives for field use.

5.4*.6.1 Clean the surface with methyl ethyl ketone, then wash With acetone. Immerse the metal in oi wash the surface wih.either: (a) 15 parts by weight ferric, chloride, 30 parts by weight.concentrated nitric acid, and 200 parts by weight clean water; or (b) 20 parts by Weight

.ferric chloride, 50 parts by weight concentrated hydro-chloric acid, and 30 parts by weight'clean Water. The sur-,

faces shbuld.be washed or iifmersed'in. either of the*

above two solutions for 2 or 3 min, then rinsed tho-roughly with clean water and dried, The 'cleaned pre-pared surface should be bonded or primed as soon as possible. The above concentrated 'acids. should be handled with caution. They emit acrid fuimes,and can cause skin buins; 5.44.62 Copper is also r6eadily cleaned With household ammonia (aqueous ammonia) which is more readily handled' safely than are the foregoing acid compounds. The 'suiface must be:washed *s before.

5.4.4.7',Hazdrds --. Many -of the solvents-and chemi-cals used for preparing metal'surfaces are' toxic, volatile, flammable or all-three. Precautions associated with the particular materials used slhould be studied and. carefully followed.

5.4.5 Wood Surfaces -- Epoxy resin systems.bond Very well to wood surfaces. The surface of the Wood should be free'of sandirig Or filling dust. Such, dust may 'be cleaned frofi the wood by wiping' with an alcohol soaked. rag or by a*n air jet.

In some woods and in some hu'mid locations this de-gree of dryness7 may produce crcking of the wood and therefore be impractical... In such cases, tests should. be made to determine: the!lowest acceptable moisture'.con-ient towhich the wood can be temporarily subjected and.

the epoxy formulator apprised of the existeence of mois-ture "in the application to obtain the best.adhesive for the job. Before 'application, the Wood surface should be filed With' a' rough file or raspý Fine-filing or sanding is' not' desirable:sihce 'it will tend to fill the wood pores and inhibit thorough. wetting: by the epoxyý Allfiling residue.

must 'be 'removed before, the application of bonding agents.

5.5,-- Temperatriie Conditioning

.5.5t --'The ease.,and effectiveiiess of epoxy application is grieatly influenced by the temperature of surfaces on which the epoxy cqmpound is apilied,Epoxy compounds commonly in use today 'react most'favorably when sub-strate' temperatures are in the range; of 0 to 140 F (- 8, to 60 C). The 'conditions uder whicih epoxy compounds areI to be employed should be anticipated and provisions made. for proper temperature conditioning of the epoxy;

.5.5.2 ý- When concrete and atmospheric temper-atures exceed 90 F (32' C), difficulties may 'be experienced in application of the epoxy compound owing t& acceleration of the'reaction and hardening rates. If ambient temper-atures are anticipated, work Ah6uld be scheduled' When the temperature is. l6we-,, such as in the' early morning houirs. At-temperatures below 40 F (4 C),. difficulties may occur due to deceleration of the reaction rates. The pre-sence of frost or'ice:crystals may also be detrimental. If it is. necessary to apply epoxycompounds, at temperatures exceeding 90 F (32 C), the Work,should be supervised by arperson experienced in applying epoxy at, high tempera-tlires. Epoxy 'systens forulated for elevated teimperature

.areavailable.

CHAPTER 6-PREPARING-EPOXY.eoMPOUND AND EPOXY MITURES FOR USE 6.1 -

General Epoxy resins and their hardefners or curing agefi-s are co-rheatiits in a.cherical reaction. The proportioning of the resin and' hardner i's -ektfeely important 'The two

.mustbe combined in very specific ratios and they musut be mixed very thoroughly to produce homogeneity within

Section Z03 503.R-14, EC 75219 ACI COMMITTEE REPORT Page 14 of 28 the mixed compoundiand insure complete, reaction. Tern-perature 6f the components of the epoxy compound can greatly affect the mixing, procedure, and teinperatuie conditioning may be required. An itemization of other handling precauftions isgivdn in ChapterO%

62 -

Temperature conditioning of material In. field Wbirkwhere low ambient temperatures xist"it is helpfil to, raise the" temperature of the: components since both thbe epoxy resin and hardener exhibit a very marked lowering, of viscosity as their temperatures rise.

The lower viscosity makes mixing much easier and faster.

A lower viscosiky also' re'duces the tendieny to whip,ir into. the compound' during miing. Components1 that are:

above. norm!all temperatures exhibit a shorened working life (pot life) of'fhae mixed compound. In this case, precooling 'of the components before, mixing may be desirable.

62.1 Epoxy.,compound components 6.2.1L1 Heating -- Several: inethtdse are available for heating"the adhesive miaterial to a tempeature where ef-fective, mixing can take plac., A. simpe method is, to storethe components indoors, in _a heated room or ware-house :overnight priorjto using and to remove them from the. heated room shortly before use. When such storage, space is not, available, or' a more rapid heating 'is Irequired, ovens can be used of 6vený'simple heated field enclosures can be built. Still anothermethod is to ira-merse the components in their containers in a.hot water bath. (see. Fig, 6'.1).

'When elevated temperature ':sourcesi are, used, care!

must be taken not.to' heat'the compone*'ts of th'-com-.

pound even locally to tempeiatifres which. might 'cduse degradation of the material. The-degfadatifdn tempeer, ature depends upon theý 9pecific comPOund. Epoxy com-ponent materials in.general use in. the, construction industry will not be harmed by tqtmperatures, as high as.

150 F (65 C). Care must be taken, however, not to short-..

en the, working life too much, by heating'the' matefial, since the 'temperature of :the mixed compound signifi-.

cantly'affedts'the Working iife'o'ipot.lifeodf the matefials.

612.1.1 Cooling" When, cooling is required.to provide adequate working life, the'following methods can be used: store. in. the shade,. store-,in -a refrigerator or refrigerated room, immerse.containers in aýbath :of cold.

water..

In no case should the material be, cooled 'to, the extefit that adequate mixing becomes'difficult below about,60 F (1s C).,

6.2 Aggregate 6.2.ý2.i.Heating-" Aggregates for'epoxy mortars or concretes are often warmed. before being-added to the epoxy compound to make, mixing easier, toýhelp. curd the epoxy mortar or concrete: more' quickly, or to, df ve, off aggregate surface: 'moisture, Aggregates,. like theý epoxy compound components, may be 'wam ed by storing in a heated building,,or by burners or radiatiri.

Care must be taken not io heat aggregates excessively because such heating can limitVthe working life 'of the.

.epoxy mortar and change the characteristics of the-cured epoxy compound The ianufacturer.'s instrUctions for the

'specific epoxy compound should.be'ollowed however in general, aggregate' temperatures over 120 F, (49 C)

ýshould be avoided.

6.2.2.2 COoling - Aggregate'which has been stored in 'the sun or has been 'dried mayb e consi4derably above normal am'bient temperature'and can' substantialy

short-

'en the 'Workihg life of epo6xy mJ'rt.r or eIpoxy' cIncriete SSpreading the aggregate 0t thin layets andstoring.in the shade Will acelelat6 coolirig.

The aggregate should not be cooled to ihe extenit that when combined with the epoxy mixing becomes difficult

'or: that condensation of moisture-fiom. the air takes place.

6.3 -. Mixing and prOportioiiiiig 6.3.1 Components Of epoxy-The required accuracy of proportioning varies'With each epoxy 'comoihond.' Some compounds can t6lerate' a wider variation but such van-ations should only be!allowed if testdata are available

'that demonstrate the complete efMct'of'ther.variation on both mechanical and chemical 'resistance properties of the cured compound..

6.3.1.1 Methods 6fptoporiioning -- The mostfacý

cui-at'e 'ethod of propoftidning is the use'o+/-' preprojpor-tioned, units supplied -by the manufacturer so tha, the entire contents of both component containers. are mixed together,.If suchfpacklaging is'l oti.available, the.compo-Fig. J.I-Heating a water bath in' which 'canis of ep'oky riesin ahd hardener can be temp'rature coiditionedho6 facilitite

,use and proper hardenihg. In' 'background wbrkmen' are brushing, on a'n epoxy grout for' bionding. niwpsltic coihcrete tO o an 'old concrete ebijion

Section Z03 EC 75219 EPOXY: COMPOUNDS Page 15 of 28 503R-S5 nents may be mixed, together in the, ratios specified by ihe'manufacturer. These ratios may be, expressed either byweight or volume.

63.1,2AAutoMatic metering -.- Automatic, metering eituipment is available which is designed seiifically for mietering Opate or liquid :adhesive componeints., These metering devices are either "shot" tYpe where successive specific quantities. of each component are dispensed or thecontinu0.us, type. where the metering device regulates the flow rate of-the epoxy components in the'proper ratio.

6.3.2 Epoxy. mortar and epoxy concrete -- Epoxy mor-tars are propor0ned by adding the mixed epoxy com,-

pound to a specified'amount of aggregate. This again:can be done either by the use. of premeasured packages or by weight or by volume.

6A4 7 Mixing.

6.4.1 General -- Mixing, of epoxy systems, must pro-duce 'a uniform :and homogeneous mix.

6.4C2 Components of epoxy -- Thqecomponents of the epoxy compound are first mixed inma manner which pro-yides stiriang or agitation which.will effectively~put them, intoa solution.together.

674.2.1 Batch mixing --.

The normal methods of providing te reuired agitation in small containers (one" quat) (One. liter) involve the use' of. s 1atulas,,

palette knives, or si'il!ar-devices. For larger volumes, a mechani-cally driven tumbling type mixer is desirable (seejFig.

6.2) A paint mixing paddle driven.by a low, speed*electric' drill (see Fig. 6.3) may be used with the caution thatr, paddle type mixers' introduce air which can reduce, adhe-sionuand.strength if'cured with air still entrapped: Mixing should continue until the compound is homogeneous.

This may take from 2 to 10 min, depending upon the vis-cosity, density and flow characteristics of' the epoxy.

Paste-like materials.may 'also be.mixed on flat.- surfaces' with a. trowel by repeated straight strokes which' tend to drag-one component through the other. Many com-pounds have their" components distinctly pigmented so:

that mixing produces a third c6l&r. This is very helpful in determining when a complete mix has been achieved.

6.4.2.2 Continuous mixing -- Commercial e~quip-ment is available which will pump the epoxy compound, components through a. mixing 'head which forces. the:

,components to, blend together (see Fig. 6.4). Mixing.

heads are, frequently used. With two component ai'rleSS' spray equipment for epoxy coatings and membranes.

6,4.3 Epoxy mortar -- The',mixing of epoxy mortar

requires that'the epbxy binder, thoroughly Wet:each 'and.

every one of'the aggregate p...tices:

6.4.3.1' Hand mixing:- Although it is difficult to do, epoxy mortars.can be hand mixed, insmall "'quantities'.

using a:.spatula,6r trowel.

6.4.3.2 Mechanical, mixing - The moSt, preferred method of mixingi is by mechanical mansý. Larger quan-tities canbe 'mxed inmportland cement-drumtype mortar mixers or, a mixing unit that blends the epoxy compo-Fig. 6,2'- Rotating bucket mixing of epoxy compounds (courteSy Protex IndiutrtIies) 6a)

(b)

Fig,. 6.3 -- Mixing of epoxy system."components can be per-formed using &a blade on 'a drill Shown here are '(a)'pneu-matic and (b) electric drills, (courtesy L. Mitchell, Consul-ting Engiineer, and Sika' Chemical, Corfp.)

nients and aggregate ;together 'into a homogenobus mass.

6.4.4 Epoxy (polymer) concrete 6.44,.1 Order of addition -- Epoxy polymer con-cretes are' mixed.in a similar manner: to epoxy mortars with 'one exception. In relatively 'stiff 'mixes 'the finer.

aggregate should be added tbothemixeld epoxy binder be-foire thelargetr agate. This order of addition will help prevet,'the tendency of the rini 1t "bll" by wetting but the. finer aggregate h have more surfce area. The fin&r aggregate: should'be added. slowly.

Section Z03 EC 75219 ACI COMMITTEE REPORT Page 16 of 28 1503R-16 Fig. 6.4 - A continuous mixing head gun being used for, crack injection. Note that a th oplasti s face 'seal: vas first applied, then. through entr ports in the sealer.the gun pumps, the aadesive (courtesy Adhesives Engineering) 6.4.4.2 Avoid segregation -- Just as in pottland cement concrete and asphaltic concrete mixes,- 'care should be taken to avoid segregation of the aggregates prior to adding them to the binder material. If *s*gre-gation does occur, the epoxy polymer conicrete will not be uniform.

6.4.5,Epoxy modified.concrete 6.4.5.1 Order of addition, - Mixing order, and jmethods vary from one, product toq the -next product.

Each manufacturer's instructions should be carefully followed.

.6.5-- Cleaning of equipment 6.5.1 General,- Except in cases Where 4disposable, mixing equipment is used, special careshould be taen to preVent; the cured epoxy co mpoundifrom bonding to mix-.

ers' and containers.. There are, five general approachesý which are, used, either seiarately or:in combifiation: With one another.

'65:2 Solvents - The'most widely used cleaning meth-od is to immerse the tools and wash the containers prior to the epoxy compound gelling with strong semipolar sol-vents such as ketones and certain chlorinated solvents like methylene chloride. Mineral spirits ortoluene may also be used, with greater.safety,- although not as efficienit as the above solvents. In'each case.complete cleaning and drying are necessary before reuse. For emulsifiable epoxy.

systems, water can be substituted for solvents as a cleaning agent.

6.5.3 Strippers - Once. the. epoxy 'comPound has cured, commercial strippers may be-used which will attack the cured epoxy compound. Some epoxy corn-

.pounds are' more readily 'attacked by stfii*pe's than others.

6.5.4.Mechanical dbrasion -- Cuedl epoxy.compounds can be abraded with the use 4Of a. grinding wheel, al-though 'the process is generally slow 'if-the buildup of material is large.

6.5.5 Burning -- Most'epoxy compounds Will burn. if

• their. t emperature is riised to about 500 F (260 C). Thus, metal tools and containers, which might not be.:damaged by these temperatures caj be cleaned in this manner.. Be-cause the products of combustion, can' ý harfiii if in-haled, ventilation must be provided.

6;5.6 Preventing thebond,- An alternative techniique.

for maintaining equfipment is to prevent a bond of the cured epoxy to the tools' or containier in the. firstplace.

Rlease agents suchas drysilicone sprays, spy-on films,s and special wax emulsions_ are useful Where, excessive abrasion is, notencountered. Care; should be taken, that the type of release agent.'used does' notccontaminate the epoxy compound and interfere with proper cure, or bonding.

6.6 - Caution on solventsand.stripp'ers The common solvents and strippers may be. highly toxic and.flammibl e. The reader,isreferred to, Chapter.

9 for-a discussion of precautions which must be taken in handling these chemicals.

CHAPTER 7'-

APPLYING EPOXY COMPOUNDS 7.1 --

General considerations 7.1.1 -- The applicator' should be. assured, that the epoxy to be applied ýhas the.proper'rate of rdening and Viscosity for 'the job. 'Bothl are affected 'by ýthe tempera-ture at: Which the epoxy is, applied (Section'6.2.1),: and both can affect the ultimate thilckniess of the epoxy layer.

The amount of sag'and thickness that Will be achieved in the adhesive layer also dependspairly on whet'er it' iS applied to a, vertical surface, to 'the top of a'horizontal su rface 'or. the,bottom and, whetier. the surface is flat'or irregular.

7.1.2 -- Highly porous concretes or concrete made of very absiorptivi aggregate may absorb enough epoxy to sitave the glue line. Such concfete should be" given afirst seal coat, of the same epoxy adhesive to penetrate into the, absorptive, aggregate. Allow the seal to become tack free and' then :apply the second coat. To-assure adhesion most epoxy."manufacturers recommend that subsequent

'coats be applied within 24 hrs. If a longer time. is re-quiied before recoating, sandblast' the latco-ot to remove the gloss' and' 'immediately. apply the next coat.

7.13 - Spray applications aresuitable formany pur-poses, but they do not always estblish a full, uniform contact-as do brush and -roller applications. The brush and roller methods 'of application, are. preferred. How-ever, they iequir6 mofe time to'aoply.'an. it -is harder to rnaintain the desired thickiess of the epoxy application:

on cold surfaces.

7,44 -- Intimate. contact.: is' essential for maximum ef-fectiveness and all necessa y, measurs Ashoul be iaken, to

Section Z03 EC 75219 EPO COMPOU'NDS Page 17of28 503R-17'-

assure complete weiting. Thorough Wetting by the epoxy may be more difficult to achieve with anmepoxy mor tar or concrete than With a plain binder.

7.2 -

Specific applicati6ns 7*.21 Skid-resistant protective aggregate bqOadast, over-7.2.1.1 General r-Th 'proper'epbxy resminsystem should be',sel' ted for the expected application temper-attfres and in-service environmental conditions. The folloWing aggregates are suitable' to provide skd resis-tance: aluminum oxide, silicon carbide, silica: sand, blast; furnace slag, roofing granules, andtrap rock.

7.2.1.2 Application methods - Two acceptable ways, to apply an aggregate broadcast overiy,are ;".iiin commiorn' use.

7.2.12.1 One method is to apply one coat of mixed resin'first, using brushes, rolles, brooms, screeds,,

or spray equipment, then, Within I to 1i0 mm, broad'as-ting the aggregate by, had or machine, taking care not to cause "shoving" of the resin. from the impact (Fig.. 7.1-7.3). The aggregate determines the final -texture or-smoothness and shouid be-applied at aboiut the rate of 1.5-.14 Ib/yd2(0.8-7.3 kg/in').

712.11.2 Mnother method is to apply two or thlree coats of resin Where protective treatment is ie-quired against deicei-s or otler aggresive agents. The:

aggregate is added to the second and third coat: as iný Section T.2.1.2.1 above; When the epoxy is tack free. the excess (loose) aggregate is removed and the-next coat is applied over the remaining aggregate, encapsulating the:

aggregate. A threeq coat *system pr-ovides better Protec-tibn. This method-is knbwn as a "seeded system"'

FLJ

-i 7,

Fig. 7.2-- Squeegeeand roll on application of seal coat fol-lowed by skid res'istan layer spread by a hand seeder (cour-tesy Sika Chemical Corp.)

Fig. 7.3 -- Skid, resistant calkined bauxite: being applied by an dutouidtic seeder for improved uhiformity. off ovrage (cbUr-iesy A dhesaies Engineering) 7.2.1.3 Bridges, parking decks and payements 7.2.1.3o1 Bridge decks, parking decks., and paye-Sments have been treated or surfaced with :epoxy materials, in miany ways, These can be.categorized as:

a) Aggregate broadcast overlays (covered in Section, 7.2:1) b) Epoxy polymer motar,overlays (coyered in Sec-tion 712.2).

c) Surface and penetrating' sealants (coveed, in Sections 272. and,722) 7.2.2 Epoxy-polymer mortar bovelas

-- The general: se-Fig. 7. -- Epoxy seal and skid resistance binder coat sprayed onto pavement by automaticmixing, metering and applica-tion machine followed by sand; broadc'asting* (courtes&'.Ad hesives Efigineering,)

Section Z03 503R-18 EC 75219 ACi CoMMITTEE REPoR6R Page 18 of 28 (a) joints, ajoin*t should be..made in the epoxy oyerlay so that, -flexible joint. sealants may be used. Generally speakifgi deep h6les should1 be filled with epoxy mortar and 'properlyý compacted and the patch brought within 'A

'in. (6 mm) of the final grade before the epoxy mortar overlay is applied. The.patching procedures in Section 7.2.14 should be followed. Since. te epoxy mortar mu*s adhere ito any: patching moIrtars :used, the. recommfenda-tions of t*emanuAfturer of the patching mortar must-be followed.

1.212.2 Polymer epoxy mortars, used for overlays dcofisistof a. liquid binder filled With from 4, to 1 parts- (by Weight) of a Jradedaggregateto one part of binder. The voi o6f aggregate use depends on particle shape and v

cidharacteristics. A single gradation of fine" aggregate has been-used wiih some resin systems. Single gradation aggregate,- containa a larger volume of voids than graded aggregate. Therefore, to *obtain a.nonporous mortar when using singlegradation aggregate' high resih contents ate re*quired. From 'a theoretical tanidp6int" just enough binder should be used to fill allf'the voids in the aggfe-

.gate rix.. This amout. produces 'optimum 'physical poetelowest' cost, and lowest srnae h

ai

nmuiw ount of aggregate used js governed by the. void content of the aggregate. Forýfreeze-thaw dIurability and cemical, resistan ce,. te air voids in the, finished mortar should&.be less than 12 percent.

Tbe thermal coefficient of expansion, of epoxy resins, is, muich igreater than-that ýof concrete, but the thermal coeffic6ient of aggregate is similar to. that-of concrete; consequently the maximum quantity of aggregate cofnsis-tent with freze-thaw durability and workability should. be used to reduce the stresses that "develop between, epoxy mortar and concrete during changes in temperature.

ASTM C 884 can be used, to anticipate problems caused by the differential thermal 'expansioi and cortrac-t6on -of epoxy mortars, and portland cement concrete.

-7.22.3 The binder system. itselfconsists of two or more liquid components 'that are combined and. tho-roughly mixed prior to incorporation of the aggregate..

OnceAhe components are mixed, chemical reactions-start immediately and the"application proceedure must' be fol-lowed to complebi~n. Pot life and'working time Will vary cns iderably; depending on thie system, the temperature, and.,the handling procedure. An applicator must there-

-fore be: thoroughly familiar with the particular system

ýbei*ngTubseddbefore? attempting ar,.application of any large.

71.2A4 For any mortar system to performi itmust

.:bond strongly and permanentlyyi to the: concrete surface.

To-do' this,. it -must completelyr weithe 'surface, leaving no, volidso0r dry areas at:"the ~nterfice, 'To; assure this com-plete wetting it is~the uual practiceto apply 'a prime coat iof the, clear binder, system to the prepared -surface, just bpeior to application of the, mortar. This thin primer may applied' with rllerl by.spray equipment, or with squees 'if the~surface is r~iatively smooth Broois. and large busIhes have also-been used.

(b)

(c)

Fig. 7.4 " Mo~rtar overlay sequence: (a) 'epoxy mortar is dunped, onto primed swface, (b) mortar then troweled onto:

surface, restoring deck to grade,. (c) epoxy sel, coat is&

s4egee':d onto cured mortar s

,face,a 'sldprooffinish*

of sand broadcast bver fresh epoxy, quence for 'installing epoxy polymer mortar, overlays-is shown in Fig, 7.4.

7.2.2.! Surface eyaluation and preparation should,

'follow 'the.,same procedures as set forth, in Chapter 5.

Joints, and cracks 'should be evaluated and repaired 'as

'outlined in Section 7T2:5: In-the case Of:working-.cracks or

Section Z03 EC 75219 EPOXYf COMPOUNDS:

Page 19 of 28 503R-19 7.2.2.5 After the binder is mixed it should be added immediately to the: ag&egate in a mortar mixer. In ifimot,ý cases the aggregate specified, Will be a clean, dry, proper-lygraded si lica sand. A very wbrkabile sand'has a :small.

amount of fines passing the No. 10 (149ý-micron) sieve.

and usually has little or no material retained on, the No.

8 (2.38 mm) m sieve (see Section,.. A4,1). The, grading shou!d be uniform between these Iimits., Formulators may, supply, special sands which, they have& found to be opti-ý mum for their systems.

7.2.2.6 It-ig impottarifto0conitrol the temperatuie of the aggregate, both before mixing and duringthatpart of the mixing :cycle that precedes the addition of the binder.

If the mix gets hot.due: to the sun, hot equipment, or frictional heat from mixing, the: curing reactions Will be accelerated and premature hardening may occur. In cool' Weather the aggregate is sometimes preheated in order' to accelerate the cure. Once everything, is in the mortaf' mixer, mixing should 'continue only long enough to 'get a completely: wetted aggegate anr d iifom mix. Exten-ding' the mixing time wilI devoyop heat and shorten the,

'timeavailable for-spreadiigi Viscosity will also increae making the system less workable. As ýsoon.as mixing is

'completefthe mortar should be dumped on the' surfiace:in the area wheree.it will be applied and soread 'Out into a

'relatively thin layer. This hielps to 'dissipate exothermi6 reaction heat.and extend. Work time.

7.22.7 After the mortar is placed on.the uncured primed surface -and spread-out with rakes or hoes to the approximate thickness desired, a'vibratingizscreed oper-ating on rails.set to give the desired thickness is passed over the mortar. For bridge and parking decks and high-way pavements the resulting.surface. 'is. usually. satisfac-tory. Touchup can be. done 'with trowels if necessary. The usual practice is-to then broadcast, alight'layer of sand over the surface to eliminate any slick spots or restin-rich areas. This npt onlyimprovestihe appearance, butassures uniform antiskid ceharacteri-stics. Minimum thickness: for an overlay applied in this manner is.11/44 in. (6 mm). These guides can vary depeiding on requirements of the appli-cation and the system used.

7.12.8 In areas where it is impactical to use a screed or if a fine finish is desired, the, mortar can be.

troweled either by hand or With power'equipment. This technique approaches an art and the.variatibiis arespeci-tic for 'each formulation. The use of solvents, 'oils, 'ot.

other troweling :aids iis.. prohibited, as these mater'ials weaken the'system and,lead to early failure.

Prompt, cleanup of all equipment and tools is a, must (see -Section 6.5). As epoxy systems cure,,they become insoluble in praqtic.aly all:common solyents. if solvents are to be used, as recommended by the formulator, they must.be used before the epoxy, cures. If the epoxy 'cures On the eqdipment, cleaning must, be performed With a hammer and chisel or with bloWtorch and scraper. 'Cau-tiori in all aispects of'dleaiiuPp is emphasized (see Chapter 9).

.7.2.3 Sur-face and penetratng sealers for waterproofing

-- The sealing, of surfaces. for waterproofing'should con-forrft to ACI 51:5.1R.- Working joints should be sealed in accordance with ACI 504R., If there are ciacks that. re-quire repair by epoxy compounds before sealing the sur-face, they should be repaired, in accordance with' appro-priate proyisions of Section 7.2..

7.2*. aPatching 7.2.4.1 Epoxy patches may be.used.eitherto repair

,an exposed suifaceor'.toPrepaie a surface to receive an epoxy 6verlay. For thin 'patches'"a sand shlould be added t6o theZepoky,thaf has a gradation falling within the. range.

given' in.Table 7.1. For. patches of 44 in. (

mm)or greater' thickness the sand should be combined with a, coarse' aggregate Whose maximum size is one-third -the thickness of the patch or less. The use of-coarse aggre-

,gate reduces the coefficient, of thermial expansion. The binder to aggregate ratio, parts by Volume,: is generally less th,n 1.6, depending on the grading' of aggregate.

Table, 7.1 -- Sand grading for thin epoxy'patches 7.-2,42..The following steps should be followed:

7.2.4.2.1 Prepare patch areas' following guide-lines given in Chapter 5, extending the newly-exposed abiasive blasted suirface beyond the patch 'perimeter by 1ft (300 mm).

7.2.4.2.2 Prime all newlyý.chi pped or abrasive-blasted concrete with the neatbinder epoxy. Evenly apply

'the 'epoxy to wet all surfaces iniciding 'the-'stee-p sides and the reinforcement steel. Do~not allow, the epoxy to puddle 'in the low areas of the hole. The epoxy mortar must be placed before the prime coat becomes tack free.

7.2.4.2.3 Place the mixed epoxy patching mater-ialiin the hole. If the depth of the hole,1is greater than. 6 in. (150 mm)j place each lift no'thicker thah 6 in. (150' dim) and 'allow lift to 'cool before'-placing'the next lift.

Ti,6wling of each lift is not niecessary. On the final lift, place'the' epoxy mortar thicker than'the surrounding conri-creje edges. Compact and screed the surface. For smoother surfaces, trowel the epoxy uitil dhe desired smoothness isq obtained. Follow the epoxy manufacturer's recommendationfor the' maximum' depthof lift and, max-imum Jtime-of application between lifts.' If the -maximum time is exceeded, then the surface of'the previous lift minay require mechanical abrasion,.

7.2.4.2.4 All texturing of the epoxy surface should be ;accbimplisfied. by he screding or troweling techniques, not by adding sand to the. uncured epoxy mortar. Sprinkling sand on. the surface of the -patch' to

Section Z03 EC 75219 ACI COMMIT-TEE REPORT Page 20 of 28 503R-20 proyide added skid properties often shows rubber build-up faster than the surroiumnding surfaces.

7.2.4.3 When a faster cured patching system-is required, select a product 'that has the desired capa-bilities. Heatifig, 0fthe cdnciete surface of the newly placed' epoxy mortar.to shorten the, cure time is often less thancost effective. Curing the epoxy below the maný ufacturer's recommended low. cure itemperatureiwill probably result in failure, Followi* the mfianufacturr8's:

instructions for bestlresults.

7.2.4.4 On vertical or, overhead rtp'airs, s§61t6 an epoxy 'mortar that is capable. of lhgPng lip ?/ to in.

layers (19 to: 25 mm). Carefilly vfollow the epoxy manu-facturer's recommendations for temperature controls and sand gradation.

7.2.5 Grouting and sealing cracks andjoints - ACI 504R describes practices for sealing of joints, including joint design, material available, and methods,of appliý-

cation. Fig. 7.5 shows 6nemethod fdr~selhihig cracks, Be-f'ore grouting or sealing stru'cturdl cracks it should be, determined ifthe crack is; actiye. and if so, what are the

ýcauses? ACI 224 1.-,R discusses, causes-and evaluation 'of cracks 'jh hardened 0concrete. Cacks. that are active should be treated as described iirt 504R. ;However, most cracks are dormant-andshoiuld be low pressure epoxkyin-jected to fill' the, entire void and return the conicrete,ý including the reinf6rcement' steelto its original monolithic design state.

7.2.5;1. Surface.seal -.- The flirst.step in filling a crack by injecting liquid' epoxy resin adhesiveis to pro-vide 'a surface seal on iall faces 0f the crack so-that, the liquid'resin Will notieakl and flow out 6f'the,:crack prior to gelling and curing. If unexposed faces of the concrete cannot be reached, cr,ck' repair by pressure injection is extremely difficult unless% specia :steps are taken. 'Where the crack 'face cannot, be. reached but where thereý is backfill or Where a slabV'ohgrade is being repaired, -the backfill 'material or !subbase material 'is often an. adequate seal initself Thereare tWo methods used to provide this seal:

7.2.5;1.1. Rouhtg -

Creating a V-groove by routing is not required. unless the surface concrete at the edge of the' grade has deteriorated. Routing is then re-quired to remove the' deteriorated concrete down. to a.

'sound substrate. Thecrack is,vacuumed to remove debris arid dust. The stuface potts are placed and the routed void is filled With epoxy lmortar or a 'non-sag epoxy,'ad-hesiye.

7.25.1.2 Surface seal-A nOn-sagging, eipoxy adhesive 'is applie i:to, the face of the crack completely

'bridging ihe*,crack. An epoxy adhesive that s'ets at.the.

desired, interval should be selected. SlowAt6 rapid 'curing

.adhesives'are:,available' inclear or pi'gented formulas.,Ini

some, cases a thenoriplastic adhesive is used where the; sealingg material isapplied, at an eldvated 'temrnerature.-

7.2.5.2 Enptr. ports -- To inject' the adfiesive:,fiater-ial through :the surfaceý seal,, entry ports must be pro-vided. Three methods are: in general use:

(a)

Fig,. 7.54a) Prior to eracq injection holes for entry ports are, drilled 'into debris-filledcracks and vacuumed to remove, c~ntaminants,. (b) injection of epoxy compound is theh per-for/medon each part (courtesyAdhesives Engineering)

'7.2.5.2.1 Vacuum drilldholes - entry ports inser-ted ---A /hole is drilled With a vacuum chuck-or core bit over the crack -to a depth of. 1/2 to 3/4 in, (13 to 19 mm).

The Mble "diameter vafies amorig dntry port 'nianufactur-ers; Most are typically about 5/8Wi'n. (r6 rm) in diameter.

It is important to select a vacuum bit thatiS compatible in -diameter size with the entry 'port diameter. 'The va-cuum bit 'is attached to a vacuum chuck, which. has 'an

ýexit port to which a vacuum hose. connecting to a-wet-dry.

vaccuum unit. is attached. As the. hole.is being. drilled, all

,dust and debris are removed from the hole during the drilliig' rocess, leaving, a clean, iuncfitainitated open crack. After drilling, ihe entry portJis placed into the hole andlhe entjre exposed crack surface sealed and' all:enry ports are.,anchored with.an epoxy'adhesive.

7.2.5.2.2 Bonded fluh fiting _. When-the cracks ae V-grboved or the concrete' suirface: is, wet, a'method frequently used is to place.anerintly port called a.tee'over the crack. The tee is bonded to theeofitrfete surface with

'the eip'oy adhesive *at 'the time of covering the entire.

crack with the surface sealer.

Section Z03 EC 75219 EPOXY COMPOUNDS Page 21 of 28 503R-21 7.2.5.2.3 Interrption in seal--

-- Another' system of providing entry, is to omit, the*,seal' from a portionof the'crack. This method can be used when special gskei devices-are available that cover the unsealed portion of the crack and allow injection of the adhesiVe.'directly into the crack without leaking.

7.2.5.3 Mixing the surface seal ahnd-injection adhesives

-- This is done either by batch or continuoC: methods.

In batch niixing eepoy components are premixed ac-cording to the manufacturer's instructions, usually with the use -,of a mechanical stirreri like a paint mixing paddle. Care. must be taken to mix only the.amount of epoxy that can be--used before the material begins to gel.

When the epoxy material beginis, to gel, its flow char-actefistics change. and piessure injection becomes. more anid more difficult. In the continuous mixing system the two liquid epoxy components pass through positive displacement metering pumps, prior to passing through.

ýan automatic mixing head. This 'system allows 'the use of fast;-setting adhesiVes that have a short pot life.

7.2.5.4 Pumping the injection adhesive - To fully filitthe crack Withcmixed injection adhesive, some nieans of proViding-pressue and flow is,required. The following, methods are typical.

7.2.5A41 Pressurepoi - A fteouently used meth-od is~that of forcing,:the material with air pressure, from a standard paint pressure, pot through hoses -into the entry port. The injection adhesive may:be placed.in a:dis-iposable container within the paint pot.

7.2.5.4.2 Cduilking gun; 'air br, hand a~tudted--A common method,'isAot use.caulkidng gun cartridge filled' with mixed adhesives.

7.2.5.4.3 Pumps,--Another method.is to p-mp the, injection.components, separately through positive. dis-placement pumps; The resin*and curing agent can be.ei-ther gravity-fed or force-fed to the:. pumps. The pumps force the individIualeloxy comPonents-through the hdses to a hand-held mixig chamber that p'operly mikes the.

material into the finished curable adhesive. Thismethod ofpumreping-and mixing eliminates problems caused by short pot life.

72.5.5 Injecting 'the adhesive -- The mixed adhesive enters the injection port through a 'connection, fitting.

appropriate to the' type of port fitting Which has been attached to, the conicrete. The adhesive is iinjected into the crack through successive"adjcentý'pois' Care must be taken to -inject the adhesive at such a rate that the pres-sure required to inject does not exceed that pressure which the surface seal can,tolerate. or Which might damage the structure. Low pressure pumping, typically' in the range of 14. to 21 psi (1 -to l1/2 MPa), is'desirable to properly alloW the entire fissure to be filled.

7.2.5.5.1 Horizontal surfaces -- In a horizontal member, such'as 4 floor, inj ection proceeds 'from, one end of the crack to the other; throukghadja'cent ports. When possible, the c¥rack is injected fromt h bottbo

'of the horizontal, concrete member filling upward.

7.2.5.5.2 Vertical surfaces, -- in vertical surfaces the injection takes' place from. the, bottom up through adjacent ports. Care must b&etaken riot to erf*tap air or water.in the crack during ihe-filling process.

7.2.5.6 Makingz sure-ihe crack, is filled During injection operations ittis very difficult to be sure that the.

crack is completely filled. Personal experience0of the ap-plicator and. low pressureipumping technques are,,very important, Ultrasonic -testing' methods,to :determine whether the crack has been filled have been perfected but the limited digseminati'on of this technolngy'restricts the'availability of this control method. The only practical method widely available isby drilling concretetcores. One or the other 'of 'these methods is absolutely necessary when assurance of a,sound structural bond 'is required.

7.2.5.6.1 Order 'Of injection - The crack must always be -filled through successive ports starting With the lowest one. Injection 'must continue through one port.

until the epoxy adhesive starts flowing oit of the adjacet port in %a steady stream without air or, water.

, :this.

point, the first ýport must 'be capped ýoff and injection started on the port Which has begun'to show adhesive.

712.5.6.2 Location of ports' -' Entry.ports should be spaced far enough apart toassiure that, when the,'adhe-siveý'material shows at.the: djaceutv'port it hascompletely filed the.cr&ack to' its 'fill d'eot., Normally'theI would be.

spaced about as far apart as-the depth of penetration, desiredý 7.2.5.6.3%Calculation oftheoretical amount. re-quired ---. A useful technique, in helping' to indicate whether the crack is filled is to estimate the theoretical void by measuring-the widthiof the,crack and the dimen-.

siohn of the, concrete memlber. Inijection pioceeds until

'the theoretical amount 'has; entered the crack. plus an allowance (50, percent add itional: has proved suitabl'). If the theoretical amount cannot.be injected, the cause should be detetmiihed, Thepossibility of undetected voids of undetermined size conhecting with a. crack' must be recognized and the gross amouht of rriaterial to be in-jected determined and limited.

71285.6.4 Maintaining pressure -- If'puimpin'g pressure cannot: be maintained in a crack that is other-wise apparently full, the reason should be, determined.

Inability to mainitain pressure indicates that the 'adhesive.

triaterial could be leaking out through a broken seal or vent'hole, or could bedra-inig into connected craikS, or

'passing through the member into. voids on the other side.

7.2.5J. Removing the surface seal -- After. the iri-

"jected adhesive has cured. the surface seal should be: re-moved by grinding or whatever means arenecessary. Fit-tings and::lioles at' entry. portsshould be painted With an epoxy patching compound.

7.2.5.8-Adhesive properties -- Ideally, the adhesive used should be comp unded for prssure i-jecti!n into cracked concrete. It shtuld be ptumipiabl6, be :readily as-similated into small :cracks by capillary acion, and should have the'caability o bonding to'wei concrete above 3:3 F (1 C). On dry concrete, suifaces it 'shouldalsobe cap-:

Section Z03 EC 7521_9 ACI COMMITTEE REPORT Page 22 of 28 603RW22 able of wetting out a. layer of dust or. coh)rete fines that

,might exist inside Athe crack. Itshouldialso, be capable of

,maintaining a low Vis§csity when pumped into colder (0 F [-18 C]) concrete andf6liy cdure _at the owest sub-strate temperature during; the curing period. The best bond is obtained to dry crack surfaces.'

7.2.5.9 Cbntaminated cracks -. Cracks Which have been contaminated with oils, grease, food particles or chemicals present special problems. Unless thecrack can be cleaned sufficiently, to allow adequate, adhesive pene-

-tration and, bond, pressure grouting will not be, an effecltive repairprocedure.

Dirt or fine particles of concrete also prevent perie-tration. They mustbe remioved.in-larger. cracks by'.flush-ing with-water,, followed by di'yihig or blown out using compressed air.

7.2.6 Bonding fresh concrete: to hardened concrete 7.2.61 General 7.2.6.1.1 -- Epoxy bond coats must be-manu-factured specifically,fr the purpose of bonding,fresh portland cement cohcte6t to existing hardened oncrtete.

They 4§should be thixotropic (to ayoid pooling) and able, to hold at leas a 15 mil (0.4 mm) film without sagging. AI-though an epoxy bond coat. will provide satisfactory adhe sion prior to the time the film,is tacky to the finger, it usually is desirable to 'delay placement of new concrete until somedegree of tack, has developed. (Note: When vibrators afetused,it is essential to0all*w therepoky bonid coat to: reach an appreciable tack, since vibration can, 'b emuisifying a fluid epoxy bond coat, displace: it from the, existing concrete to. the detriment of the bond.) If, inad-vertently, the epoxy bond,coat reaches a. soft rubber-like

.stage"(no tack) prior to the placement. of the new port7 land cement concrete, a second application ofthe,epoxy bond coat is required. Also a. highly viscous bond coat may not adequatiely pienetrate 'the base concrete and evertual bond :strength will be 'ruuce* The onrcr&ee should be a non'bleeding mix of not more 'thah' 2 in.

(5.0 mm):slump for best results,,

7.2.6.2 Formed concrete -- The concrete 'surface should be prepared as in Section 5.4; Forms suitablefor placement of the new concrete should be made in a way that permits.them to be.assembled and put in place with-in the time limit, imposed by the.gel time of the epoxy bond coat. Theý epoxyshould be mixed in the proportions recommended. by the manUfacturer,, and applied with,ja stiff brush roller or spray equipment Sufficient force should be used to assure thorough:and complete wetting of'the concrete and exposed aggregate. Coating of the reinforcing steel improves adhesion and pfovides added protection. The forms should then be placed, and filled with portland cement concrete, in. 'the usual mannei, before ihe epoxy becomes iack-free.

7.2.7 Bonding'htrdened concrete. to hardened' concrete 17.2.7.1. Before bonding, both surfaces should be thoroughly cleaned -and both should.be dry (see Chapter 5). Epoxy compound should be applied to::both surfaces.

If the surfaces are vertical, thixtr*pic, epoxy compound should b*e use~d. The..compound -should be worked,,into

the surfaces thoroughly with a brush. Fo.r, horiontal

-surfaces:an epoxy':should be~used which is'0so formulateed

.as to be,,absorbedto a greater depth. Itcan be applied by brush,. roller, or spray.

7.2.7.2. The surfaces should be pushed firmly to-gether, and clamped in place, if thereis any. likelihood of

,moVement in the first--several hours. Prdvision should be made to prevent any leakage from 'the joint. during: the hardening 'period.

j'.218 Reflectorzed traffc' points -Sometraffic pa.ints are, :essentially pigmented adhesives ýfor bonding glass, beads or ieflecting,aggregate. These,Ashould.be applied to cleani dry surfaces tdirig a_'pefiod When traffiCd can be kept off the pavement for a period sufficient for the epoxy to attain soime. strength -- usually a minimum of about 3 hr. The normal coverage should be. about. 100 ftW/

gal. (2.5 m2/L). About 6 lb (2.7 kg) of glass beads should be, eenly distributed, over 1.:00 ftz'(9.3 i 2) of" fresh paint.

17.2`9 'Coatings to prevent c'homical 'attack r-When epoxies are'used as coating, they.Ahuld.'be used in accor-dance. withACI 515.1R.

7.2,10 Bonding concriete, to steel -- BWfore applying epoxyto steel., tlhe steel inust be, prepared as detaile'd in Section 5.4. The epoxy should, be applied to.the steel if Ait is to. be: bonded.to'fiesh concrete, and the concrete placed 'while',the epoxyis still, tacky, as in Section 7.216.

If the steel is to 'be ýbonded to' hardened concrete, the

• epoy should beapplied to'-both' surfaceds..The materials should be clamped or held 'togther,with jat suffi'ient force to. prevent-movement.duing haidegiingI Excessive force should be avoided 'to hi-event

'intrloliction of stresses when ihe'clamps are removed. Provision should be made to prevent: epoxy -from running out of the j'oint.

7.2.1i Bonding& doncrete to aluminum n-Aluminum surfaces should be`prepared as inSection5.4.4. The same procedures. are.used 'as in bonding cncrete to steel. It

,should be Nfite, however, that :'lumin umis'.susceptible to attack by the alkalies of-cohcreieas well as by calcium

'chloride 'if it is. present. Such attack.can"be prevented in most circumstances by insuring a pinhole-free film, onthe

,aluminum surface; TWO coats should first be applied to the aluminum and allowed to :'set' before applying the coat that bondsit to the concrete. The Secoind and third coafings should be ýapplied while, the, previous one is still tacky. Uncoated aluminum must never be allowed to

'come into contact with rpinforcihng steel.;in concrete, 'be-cause it sets up :a 'galvanic couple that results in corrosion of metal -followed by fractanre' of the.concrete..

7-.2.12 Bonding coticiete, to:other metals.,- Other me-tAls'to be bonded 'to concrete should be p]repared.'as in' Section.5.4.4. Precautions should be, taken 'to prevent galvanic couples (setion,7.12. f). Epoxy should be ap-plied, intimately to the surface., Fresh concrete, or hardened concrete with a freshly appliedd epoxy coating, should.be brought, into'contact with ithe prepared surface while the epoxy is still tacky; An eXail'le of bonding con-crete to metal is. shown in. Fig. 7.6;

Section Z03 EC 75219 EPOXY COMPOUNDS Page 23 of 28 593R-23 Fig. 7.6 E-mbedment of center line lighing in runway Holes were cored, mixed epoxy poured iherein and the light qnd junction boxes set and grouted (courtesy Adhes ives Engineering) 7.2.13 Bonding concrete, to wood- ", For'surface Piepa-ration, see Section 5.4.5ý The-epoxy should be applied4to both lthe wood surface and the coencrete* surface iff the,

'wood is to býeh onded'to hardeened con rete. If it is -to be.

bonded tofresh, concrete, the epoxy:should be applied. to the wood surface. The wood should be*.protected against absorption ofmoisture during the concreting operation so 'that. no dimensional changes will occur in it-at this, time. Because of high'volume chiangeson alternate cycles of wettifig a.d drying some woodsg are n0s.§uitable for bonding to concrete.

7.2.14 Bondig concrete to, plastics Bonding concrete to plastics, presents special problems. Tests should be made to determine how bond can.best be.obtained, and, consultations :held With the manUfacturers.

7.3 - Underwater applications With mostffrmulations bonding can. be achieved best

,under dry c rnditions. When dewatering and surface :diryý ingof thes-oncrete is not possible, special epokies should be chosen. Some, can be applied directly-to surfaces while, they.are underwater. Prepration'lshould include trial ap-plications-by the user and subsequent: testing of bond

'fesults since application techniques are, critical in most cases.

CHRAPTER 8 -- HtARDbE'NIN'G 8.1 -- Rate.-of hardening 8.1.1 - Epoxy compounds areavailable with ai Wide range of hardening rates; varyVa ing from a few minutes to

several weelki For use with portland :cemenht concrete, the six following classes of epbxy compoundsare desig-nated'in ASTM C 881.

Tvpe,I through V Class A:

For use below 40 F (4.5 C)

Class B:.For use between 40 and 60,,F (4.5 to 16 C)

Class c:

For use above 60 F (16 C)

Types VI and VII Class D:

For use betWeen 40 and 65 F (4.5 and Class E.

For use between 60 and 80 F (15.5 and 26.5 C)

Class F:

For use. between 75 and 90 F (24.0 and 32.0 C)

The.temperatures indicated for each class refer to the

temperature ofthe concrete substrate. The use of these materials :outsid*e thei desi-nated.t emperAture range is discussed, in Section 8.2..

8.1.2 T-The, most important factors influencing the rate of hardening,; other' thani the composition. of the com-

lotondarý temperatiire of the concreteý substrate, the. air temperature, and the temperature attained by the mixed compound. As soon asý the epoxy resin and hardener are mixed together the. hardening, reaction begins-. If the mix-ture, is allowed to remain min a mass, the, heat of, reaction canndt escape 'and;.consequently,tiie temperature of the mass increases, accelerating the' reaction.. As soon as the epoxy compouhd has been spread, it rapidly, acquires, the temperature of the surface onto:. which-it wa's spread and

Section Z03 S03R244

,A i COM MITEC 752R 19R

A-ICOMMITTEE REPORT Page 24 of 28 is greatly influenced by the tempiratire. ofthe air to which it. is exposed.

8.13-= Tol obtain the desired reactio i is important first to. select ;the proper class oftcompound; second; to adequately mix the compound, While maintain-ing:a minimum-thickhess'of material by* proper selection of a mixifng c6ntainer; third, to spiead the mixed com-pound on a 'surfaCe having a tempeture within the desired range; and finally, to expose to air temperatures within the desired' range.

8.2 -, Adjusting thehardening rate, 8.2.1,-

Natural. environmentai conditiois Will nIot always be such that' theconcrete,surfices (to a depth of about:3 in. or 7.5 nm) and thle.air and,epoxy tempera-.

tures are Within the optimum range, f6r the-application" Preheating or cooling the surface tO a satisfactory tem-perature, preheating or cooling the epoxy compound.con-stituents before mixing, or both will then be' necessary.

Preheating the epoxy, compound will increase..its:*hard-

'ening rate thereby shortening the period available for, appiicati6n. Excessiveý.preheating miaylshorten the appli-

,cation period to theextent that proper aploi cation ca.nnot be accomplished thereby rg`ulin" in`

'oorb6nd. Precool-iing the epoxy ormpound will increase its viscosity consis-tent with the, amount of temperature, reduction. The

-more viscous. the material, the more. difficult it iis to

.properly apply. Excessive precoolirng can increase the

,Vic'Sosity'Ato the extent that the mixed epoxy compound cannot completely Wet the surface -thereby resulting in poor bond. The foimulator's recofnmerided ternierature

'`ranige'for miixing the epoxy compound-should be followed for.all, field rapplications.

8.2.2 Accelera'ion of.hardening raie - An accelerated hardening rate will be needed: When, the. concrete surface and air tempeiaturesare 'uiaVoidably below the proper temiperatufe range for the class of epoxy 'cofripounds chosen for the project. Many methods and combinations of'methods can be devised, but most are impractical for large -areas over thick concrete. The following are methods used; for a ccelerating, the hardening rate:

82121,i Infrared.heaters wto preheat the concrete surface and also to heat the epoxy c'mpouftd after it is

spread, 8.2.2.2 An/'inclosure heated by circulating warm air, 8.2.23 'Clear Polyethylene film."'placed over the completed j`b,

&2.24 Heated oaggregate.-mixed with the prepared compound in. producing epoxy. -mortar or concrete; In any'event, uniform heating [notvover 125 F (51 C)]

is essential, and dii~et;tflme. heating is'prohibited.

8,2,3'Deceleraiion of hardlening rqte - A decelerated hardening. rate: is: needed whenthe concrete surface and air temperaturs are inadvertently above the proper. tem-perature range for the class of epoxy compounds chosen

'for 'the project. The following methods.have.been used to decelerate the, hardening rate:

8.2.3.i Prototion of the application area; from direct sunlight prior to, durg, And."after applicition of the mixed compo-und.

8.2.13.2 Use ofice bathtO. lower the temperaturedof the components before mixing.

8.2.33 Rapid spreadingiof the mixed compound-in.

a thin, film.

8.3 -- Op-eningtllejobto servie The strength requitrements of the epoxy compound will differ with each end use. In mahy insta*ces, theý surface f-r the cured epoxy. compound: is.. not accessible forý evaluation of the degree of hardness and strength attained. Therefore, it is*, necessary: to" rely' on the

,supeMsor's judgtnentý,and' ep'eridnce.- and on the,'manu-factuite's data as. 'to the,'anticipated strength. For some purposesi it is necessary for the epoxy compound to achieve almost full strength before opening the project to.

servicean.d the time required.mightbe only a few hours at summer. temperatures.

CHAPTER 9 - HANDLING PRECAUTIONS 9.1 -

Ge-heral 'hazards 9,-1.1 Just as there are proper,-safe practices for handling lime, acid, porand cement, etc., there are also precautions. Which should be observed' when handling

,epoxy resins and materials used with them..

S9.1.2 -- A number of different basic epoxy resins can be combined With an even greater iuinber of cutiing. agents, flexibilizers, fillets and other chemii~als to: produce several hiuidired'hdifferent end*ý rod 'ts with varidus com-binations of 'their unique prop.rties. This-versatiiity, which makes the, epoxies so useful, also contributes to handling problems 'for the user (and,. indeed,. the manu-facture$)"- of epoxy products. On the one hand; a few epoxy formulations are nonhazardous; on the other hand, there are a few formulations 'which are extremely hiaar-dous; and in between are compounds with varying degees, of hazard.

9.1.3 -. Two typical health problems which: may be en-c'untered When epoxy' materials re' carelessly handledl are:

9.1.3.1 Skin irritation; suchý.as 'bums, rashes, and itches.'

9%1.32: Skin sensitization, which is an allergic reac-tion similar to that caused in. certain people by wool, strawberries, poison ivy, or ot.er allergens.

9.1.4'-- It'should. be noted that sensitization reactions may sometimes occur immediately, but at other times they occur only after long periods of continual exposure.

Workers should be aware, of th&e possibility of'delayed sensitizaatidn a

,d not" assume that they -arIe immune.

941.5-The variety of th~eepoxy compounds marketed today make Iit.essential that the labels and Material Safety Data (MSDS)* she~ets., be read and' understood by those: people work ing with:the products. Code.of Federal Regulations (CFR) '16, Part, 1.500 reguiates.the labeling

Section Z03 EC 75219 EPOXY COMPOUNDS Page 25 of 28 503R-25:

of hazardous substances including epoxy compounds.

ANSI standards: ANSI Z 129.1 and. ANSI K 68.1 provide fuirther guidance' regarding.classification, and precautions.

9.1.6'-- Many epoxy resin formulations are classified as "Corrosive"' o#"fan al"i 49 CFR Transportation Subcapter C "ýHazardous Materials Regulatio'n's." I Pack-aging, labeling,, atnd shipping. f0r. such materials is con-trolled 'by' 49 CFR ITransportation.

9.2 - Safe, handling.

Safe handling of epoxy materials can be accomplished 9.2.1'- Working inf a well-ventilated area. As with most chemicals, materials should be stored below eye level.

9.2.2 --,Disposable suits and gloves, available from many suppliers of work garments; are suitable for this

use. Gloves should be tested.for resistance to resins and

!solvents. Disposable ]ubber o.r plastic gloves are'rec6mi-..

mended and shouldb*e discarded after each use., Glves should be tested foir resistance to resins and solventis Cotton gloves, if used, should never 'be reused if they have become soiled W ith epoxy compounds.

9.2-3 -'- Careful attention' to personal cleanliness and protection. Safety eye-glasses or goggles :are :strongly

.recommended bothwhen handling epoxy compotunds and

'acids. Involuntary habits such as. face scratching:or eye-glass adjustment should be avoided. Foir similar"reasons,

handling important tools, eating. or smoking should not obe done' untilt.he, ndiv.dual ha washed up.

ien weaý-

ing soiled gloves, the workers should,avoid touching door handles and otherequipment' which may subsequently-be touched by a person not wearing gloves.

9.2.4 Federal regidatiOns -- CFR 29, Part 1910 (OSHA Standards) regulate handling of hazardous substances including epoxy compounds.

9.3 -- What to do in case of direct contact 9.3.1 To the clothing -- Remove soiled clothing at, once and changeto 'clean garments. If the 'soiled garment cannot be thoroughly cleaned, it shoild be destroyed.

9.3.2 To the body -- Shower immediately,withi 'soap and water'to remove. pilled epoxy c6mpouinds f*ro ie body. Avoid c Ontact Vwith the genital areas until after the hands are carefully,.cleaned of all epoxy-.

9.3.3 To the eyes'- Flush out With large amounts; of water for at least 15. min,, followed by immediate medical attention. (Safety goggles Will usually preent getting chemicals into eyes:)

9.3.4 Oiher places -- Do not use' solvenits.other than soap and water or water soluble proprietary cleaners.

Most solvents merely dilute the epoxy compounds, aiding them, in vpen etating-the skin.. At ihe same time, solvents tend to.cIdry.oute skin and any subsequent exposure is more likely to cause problems.

9.4 - Use of solvenit 9.4.1 General -- The epoxy compIourids considered fdr concrete applications. are usually solvent free. However, solvents may be used as a convenience, for cleanup of equipment. and areas on which, epoxies might be spilled.

Thl.e.solvents 'used Will re-quifre' additiontal 'precautions depeniding, on, the characteristics of the type used. It is generally' "true that'soliv§ent* should-ffnot be Used to remove epoxY products fiom thee lfin. They tend 'to'dry the skin and may. themselves cause dermaifitis. AdditionallyJthey dissolve the epoxy compoun ancarry it into more jitit-matecontact wiih the skin, 'thuS aggrayating ihe dermatit-

!c problems whichalready exist due to. skin :contactwith the epoxy compound. The 'following hazards might be en-countered in the use of s61veits and should be 'taken into consideration. it may be emh'asized that' when using a, solvent, the combined' hazards of both the solVent and the epoxy compound are encountered.

9.4.1..1 Flammability and exploSion hazard -- Many solvents having low, flash points"'are tot, recommended and should be avoided,. Cleaning'solvents.such as ketones are red label materialsard,.present a fire hazard. If used, adequate ventilatibn should be proVided, equipmaent should be 'grounded and smoking or other fire initiating devices Should be barred fromh the.area 6f use. The chlor-

,inated solvents, While.not representinga.fire hazard, will present: a toxicological problem if a person smokes in their presence or.if a fire Occurs in the immediate area.

9.4.1.2 Vapor hazard --,,Most, solvents. have some,

'degree of volatility and the vapors -can be 'toxic: when inhaled Avoid. usinig, §'sovenis Which may be harmful.

9:4413 Contact hazard -- Some cleanup solutions:

contain phenols orother very aggressive chemicdls w~hich

,can. cause bums or other serious effects when contacting

,any part, of the body directly or indirectly. Use:"such materials with great care following the recoiimnendations of the supplier.

"9.4..1.4 Dispose of spenit solvenftsin accordance with local and federal regulations.

9.5 -

Education of personnel.

No amount of equipment will "substitute for worker ed'ucdAtion:, Those involVed in Using' epoxy materials should be thoroughly informed' of the characteristics and

'hazards ofthe particular i'rnferiAls they must handle. Not only label instructions bu a* the manufacturer' s. iter-ature and MSiDS sheets-should be reviewed and pertinent information passed on Ito eeach workeIr. 'The hand)ling of

,epoxy materials is not a dangerous occupation as long-as

.reasonable care. is taken.and' personnel and equipment are kept clean. Instances 'of sensitization' are rareb

-6it-the possibility of abum, a damaged eye, or other loss-of-time accidents makes'knowledge and

• bservance of safe hand-ling practices absolutely 'essential. A sensitized person must. not be 'allowed to c ntinue working. with epoxY materials,.

APPENDIX A-TET METHODS Al1 - Field test for 'surfaice ýsoundness anid adhesion

Section Z03 EC 75219 ACI COMMITTEE REPORT Page 26 of 28 503R-26 A.! -- Clean a portion of the area to which the epoxy compound-is to be applied-according to prescribed clean-ing methods'. The area 'seleCted for. tesiing 'should represent, the..worst-of surface conditions within the-area to,be repaired,. The test area should be',large enough. so that -the cleaning equiPment and methods of cle,_ning to be employed in-full scale, operation, may 'be used. This avoids. the possibility of attaining a degree of cleanliness in a small test area 'which could 'riot be' matched later with the, equipent to be used on a 'continuing basis; The surface muist be. thoroughly dry before undertaking Step A.12.

A.12.. Mix materials and appiy a.testpatch according to applicable procedures of Chapters' 6 and 7 usingthe epoxy compound-to be used in'the work.. The test patch should coveit enough of the surface: to include all the typical surface conditions found ih the largert areas to be covered. For example, in a warehouse sUbjecied to Con-siderable forklift truck traffic, the test patch should span a line to include the wheel tracks where:appliedl oad and wear are most severe, -and the center areas where.deposi-tion of oil and traffic soil is heaviest.

A.1.3 -- After the.-test, patch has hardened, core-drill through the coating and d6wn barely intothe subsurface.

by-means-,of h electricdrill fitted with a.carbide-tipped or, diamond core bit (Fig. A. I)The, core bit should be of" such size as io produce a cored disc 2 ini. (5,cm) in. dia-meter which will have the appearance of-a smarllisland of coated Material (Fig. A.2).

A.1A - Bond a standard l/z in. (3.7 cm) diameter pipe cap, the 'bottom surface of which has been mnachined smooth and sh*ulder-cut to provide a. 2 in. (5 cm) dia-meter surface.(Fig. A,.3), to the cored disc using nearly any commercially available, room ternperaiure. rapid curing epoxy compound adhesive. Mix the epoxy compo-nents according to the supplier's recommendations~just prior.to use. -A -2 0z (50 gni) portion of this material, should have, aWorking life of 20-25 mri at 70-90 F (20-32 C). *Apply a. small amount,of the mixed adhesive to the 'c0re'd.isc and'to thebonding face of'thepipe capby spathla.

desired, the b'eonding face ma he-heated to facilitate §preiin of the Hosiye:,

H6weveri the qpedi&sip~lreadn

.9d-theives cored disc-shoul~d nev~eyrbe heated directly. Place-the pipe cap -on the-cor4ddisc. Direct a flame from a, small gaso-line blow-torch. (an electric., heatlamp or a -portable gas radiant-heater may be used as alternatives) into-the inter-ior of the'ý pipe-cap i n such a-way that no 'direct,- heat reaches the cored, disc' or the' paviement bond. line, and h eat the pipe cap to'. about 160. F (70 C)..:(This ~tempera-ture can readily ýbe, checked with a, surface pyrometer.)

Under these 'conditions the adhesive, should harden - in less than. 1 minute. The bonded cap 'will be ready for

'testing, as soon'as it-has cooled to air temperature.

A.,lS -- After cooling the pipe cap and core, test the core by applying tehsion -to'it using a testing-device simi-larto the one-:shown in Fig: A.4 and A.5.. To prepar the testing device; screw the lower '.hook into the threaded pipe cap and attach to the loop on-the lower portion -of a Dillon dynamometer. Screw the upper hook, which has a threaded shafi into the loading ann at the top of the rig, andattach,to the.loop on the upper portion of the dynamomreter-'--en fo-e-i--

pplied*,the axis of the:dy-namometer must coincide with the axis of the pipe Cap extended. Rotate the loading' ann sthat the threaded shaft and i ts, connections are lifted, placing the pipe cap (and core) in tension. Tensile load should be applied at the approximate rate of -100. lb (45 kg) every 5--sec. 'The tensile load is indicated on the Adynamometer gage.

Record the load At 'which the pipe cap and connected core is separated -from. the conci'ete, surface and convert to uniit stress.. Note the type of fa)lure ofwhich there,are three, possibili,,ties or combinations thereof:

NKIt Fig. A. I - Portdble cabide-tipped core drill in,psiiibn for ding rg'.A 4"- ".orea:aisc ajter ready for.the aitachment cap

,.rig: A.,J -- Ma~ctne jacea pIpe cap bonded-to-cored, disc with epoxy com-

,poun-d

Section Z03 EC 75219 EPOXY COMPOUNDS Page 27 of 28 503R-27 17.

-- ~-- -

-I 7':

a.-..

S I' Fig. A.5 - Functional sketch of mech-anical testing "deo ce Fig..

4,- -, Mechanical testing device for pulling bonded pipe cap in tension Fig. A.6 -a Typical failure in concrete; dark spots on cap and in aggregate in-dicate split aggregate a) Failure in the concrete (cohesive concrete failure)-

b) Separation of the epoxy compoun4 from the con-crete surface (adhesive failure):

c) Failure-in the epoxy compound (cohesivexresin -fail,

-ure)

• Record the-percent of eah.type of failure:along witf the load required to'bring,`about the failure; 'A properly formulated epoxy compoundd applied to a properly pre-pared surface should-result in a concrete. failure as shown in Fig. A.6. When the pipe cap and core have been sepa-rated from the surface, the hole created by the test-:can easily be repaired using:eitheran epoxy resin compound or the remaining epoxy adhesive if there is a, surplus.

When -the strength of a concrete surface is to be tested alone, Steps All throughAI.3 may be eliminated, ex-

,cept that a small area must be cleaned for bonding the pipe~cap, directly to the-concrete -surface. Tests should.be performed in several areas-which represent the, worst conditions, and which giveia statistical estimate'of results to be expected.

A.2 - Simplified field test for -urface soundness A.2.1 -- If this test is being employed to ascertain the need for suiface preparation and detecting relative dif-ferences in.-potential surface strength over an area to be repaired, skip to Steps, A.2.2 and A:2.3. If the,- test is employed to, ascertain* adequacy of surface, preparation, clean the. ai-rea, or portions thereof if f:a, large atea, ac'-

ýcrding to the brescribed cleAing methods, portions of large areas to. be test, cleaned should, be sufficient in number to be, representative of the ýtotal area and each portion should be large enough ýs 'So that the cleaning equipment inhtended for ihe:full scale application can be used in a stndaird cleaniing opetiion. Provision should

,be made for conducting the test -atý the rate of at least one jtestqper 1f00 ft (9.3 m2) of ar'ea to be repaired The surface to be tested, must-,be dry before proceeding with Step A2.2.

A.2-2 -- Cut:i ini. lengths ofl in. aluminum T-section to provide -a one ihn 2 boriding-surf*ae at the.bottom of

'the flange. Drill, a hole in the stern of each T-section -for subsequent attachment of the testing device.. Thoroughly clean the aluminum surface by abrading with.crocus or emery cloth being, careful to water wash and dry before, using. Bond the aluminum T-section to the concrete sur-face using a fist setting epoxy comrpound mixed juct prior to its use -in, accor&nce with the supplier's recom-mendations. This, is accomplished by applying a small quantity of. he epoxy Icompo nd Ito the concrete surface followed 'immediately by working the T-section into the epoxy:in a manner toiestablish th6rough contact between the epoxy, the concrete and: the aluminum T-section, Upon completion of this opefation, score around the per-imeterof the T-section to remove excess epoxy which has squeezed out so that the bonded.area Will be the desi-ed

• one square inch.

A.2.3 -- The f6llowing day, or as soon as the epoxy has set, attach a testing device, similar to the. one shown in Fig. A7 to the aluminum T-secfion or the-mechanical de-v-ice described in Step A.1,.5,. Apply tension at an uninter-rupted;' uniform-rite. The teilsile-o6ad 'is indicated on the dyp4ammeter gage. Rec0od-the *6ad at Which each T4sec-tion is separated from. the concrete-surface 'and express it, asunii stress. Niqte thetype-of failure, ýas~in Step A 1.5,

Section Z03 EC

-AC1,.COMMITTE 503R428

75219 Page 28 of 28 EE REPORT Ektender.- A nionreacting liquid' substance added to epoxy compounids to extend pot life, increase flexibility, and lower the cost, Flexibilizer:' A. substance, which will react. with epoxy

.ompounds to impart flexi.iliy.

Filler:.A finely divided material,, such as mica' or talc;.

incrorp6rated in an epoxy formulation to increase the hardness and lower the cost.

Hardener:, A substance4formulated so.that when mixed with an epoxy resin -it will cause the epoxy toqso!idify and harden.

Ionic: An adjective used to describe substances that.

dissolve.to form ions. jUpon dissolving, each molecule of the ionic substance:splits ito two or more ions. The ions always camr.ranelectrieal, charge,ieither positiVe or nega-.

.tive; The 06sitive and negative charges are'always equal,.

so that the"oVerall efedtrical charge, is neitral.

MAi.: ýOne-thousandth of an inch.

Non-ionic: An adjective used to describe substances that dissolve. without formation of ions. (See ionic)

Non-polar" Used. to describe molecules characterized by a uniform distribution of electrons:. so that there is essentially no6 electrical.charge, sepaation ýifi the, mole-cule. (see semi-Opolar)

Overlay: To apply a mortar to suIfficient 'hickness, usu ally *4 in. (6rk m) or more, to, form a new suuface.

(see' semi-polar)

Pot'.ife:- The period of time'during which' he.epoxy compound.is in a-,suitable condition for use, Resin motrtar: A combination of epxy 'resin and fine aggregatein'a.c6nsistency suitable for ti oeling..

Rout: To.deepen'and widen..a crack Wt prepare it for patching or sealing.

Semi-poldr: An adjective used to describe molecules that are intermediate between non-polar and poiar types.

Non-polar molecuiles 'are charactedized by a. iniform dis-tribution of electrons such that' theret is essentially. no electrical 'charge, separation in the molecule. Polar imle-cules. are cha racterized by a nonunifo distribution of electrons such that. there is a 'difference in electrical potential from one end of the molecule. to the other. Po-lar molecules tend :to have higher' sol*ent* strength 'than non-polar molecules.

Stripper." A liquid coimpound formulated to remove coatings by chemical and/or solvent adtioh.

Subs~taie: The uncoated surface upon which'a coating is applied.

Thetnoplastic plastic. A, plastic that, generally.does not retuire~curifig"agents and can be'dissoiveddina solvenit0or melted without permanent chemical change.,

The rrnoset ting plastic: A plaitic that, ofce*'curte, can-not be melted or dissolved, in a solventwi4th6ut under-going. drastic.chemical change.

ACI '503RM93w*'Wudtitted to letter ballot of the commitee.,and was aporoi'ed' according to ih iiute.- ball1ting procedures.

Fig A 7 -. Tension frame for pulling T secfions bondhed. to a surface (courtesy George W Whitesides Cod; Inc.),

APPENDIX B - TERMINOLOGY Ambient? Usually:used to describe temperatute;- mean-ing-'the same as the' su-oiindings. Ambient 'usually', but not always, implies a temperature that is in the range of 60 to90 F (15 to32 C).

Broadcast: To toss granular material, such as,sand over a horizontal surface so 'that 'a thin, uniform layer is obtained; Delamination: Loss of adhesion and separati6n be-tween coatings or betaeen a coating and its substrate'.

Diluent: A. liquid.ether which 10wers 'the viscosity o.f epoxy formulations and which reacts -chemically with them.

Epoxy concrete: A combination of epoxy resin and fine and coaise' aggre*gatedin *ahconsistehicy :similar to portland cement concrete.

Epoxy grout: A. fluid epoxy compound used to fill cracks,. set dowels, etc., in a manner si'mila-r fo conven-tional grout..

Epoxy mortar:,:See resin mortar.

PCHG-DESG Engineering Change Attachment E - Bond Test Data 0000075219R0 Use additional sheets as required.

Z04 Attachment Page I of I

PCHG-DESG Engineering Change 0000075219R0 Intentionally Left Blank - Information was removed during final review of EC product.

Page I of 1 Z05 Attachment

Section Z06 EC 75219

]eNEWPORt Virtuy Te~mperatu'r~e & Relative,Humidity Pagec 1 of al C'.hart Recorder i

Web Server' I-

.Get Alarms sby,Email or

jilt, TextIMessage No Sp'eCia*l Software Requ iTHX-SD: Record Years of ired Data on Popular'SD Cards ETHERNET RES Ci IWJP STOY WILT

'Is~everI cif I

The NEWPORT) iTHX transmitter let's you monitor and record Temperature, Relative Humidity and Dew Point over an Ethernet network or the Internet with no special software except a Web Browser.

I The iTHX serves Active Web Pages to display real time readings, display charts of temperature, humidity, and dew point or log data in standard data formats for use in a spreadsheet or data acquisition program such as Excel or Visual Basic.

MADE IN THE U.S.A.

FCC-B CE U

LISTED The virtual chart viewed on the web page is a JAVATM Applet that records a chart over the LAN or Internet in real time. With the iTHX, there is no need to invest time and money learning a proprietary software program to log or chart the data.

Section Z06 NMEWPORT.

EF 75219 Page 2of4 Soerver MicroServer iTHX Adjustable Charts Chart scales are fully adjustable on the fly. For example, the chart can display one minute, one hour, one day, one week, one month or one year. Temperature and humidity can be charted across the full span

(-40 to 1240C, and 0 to 100% RH) or within any narrow range such as (20 to 300C).

When a second sensor is added, users can select a chart that records channel 1, channel 2 or the difference of the two channels.

' 0 0 Recording; ON III 60I 1

0.1 T-eperature 108.2 F 50.8%

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A second probe can be added at the time of purchase or in the future.

NEWPORT offers a choice of industrial probes in 2" and 5" lengths, and a wand style for ambient indoor applications. A simple DB-9 "Y" connector is available for adding a second probe to model iTHX-W and iTHX-SD. No connector is required to add a second probe to the DIN rail mounted iTHX-2.

Award-winning Technology The NEWPORT iTHX is simple to install and use, and features NEWPORT's award-winning iServer technology that requires no special software except a Web Browser.

The iTHX connects to an Ethernet Network with a standard RJ45 connector and sends data in standard TCP/IP packets. It is easily configured with a simple menu using a Web Browser and can be password protected.

From within an Ethernet LAN or over the Internet, the user simply types its IP address or an easy to remember name such as "Cleanroom5" or "ServerRoom" in any Web Browser, and the iTHX serves a Web Page with the current readings.

iTHX-SD Adjustable Chart

-Display and Chart Two Channels The iTHX transmitters come complete with a temperature and humidity probe for measurement of a single location. With the addition of a second probe, the iTHX transmitter can measure and display temperature, humidity and dew point in a second location up to ten feet away.

__ Title _

Temperature 76.37 OF Humidity 59.66 %

Dewpoint 59.99 OF CH2 Temperature 75.29 OF CH2 Humidity 47.73 %

CH2 Dewpoint 53.42 OF Ma~in Men-*

Reading 2 Sensors on iTHX-W The transmitter can display and chart absolute measurements in both locations, or a differential measurement between the two locations. The second probe requires no change to the basic iTHX transmitter hardware.

NEW iTHX-SD with SD Flash Memory Card and LCD Display The NEWPORT model iTHX-SD with LCD display, adds several valuable features in addition to the backlit local display of temperature and humidity.

The iTHX-SD comes complete with a removable 2 GB SD Flash Memory card that can store up to seven years of readings taken at ten second intervals.

The data recorded on the SD card can be read with a standard card reader or remotely over an Ethernet network or the Internet.

With data being recorded on the SD card, a failure on the Ethernet network will not interrupt the data recording.

Alarm Relays The iTHX-SD features two 1.5 Amp relays. With the easy Web-based setup page, the two relays can be programmed for any combination of temperature or humidity, and high or low set points. The relays can also be programmed to remain latched and require a manual reset if a limit is exceeded.

Battery Backup The iTHX-SD comes with a universal 100 to 240 Vac power adapter.

A standard 9 Volt Alkaline battery (also included) allows the device to log data for up to 2 days without external ac power.

Email Alarms All NEWPORT iTHX models that are on a LAN that is connected to the Internet can trigger an alarm that can be sent by email to a user or a distribution list anywhere in the world, including text messages to cell phones and PDA's.

Typical Applications The iTHX is great for monitoring temperature + humidity in applications such as: clean rooms, computer rooms, HVAC systems, pharmaceutical and food processing and storage, hospitals, laboratories, semiconductor fabs, electronic assembly, warehousing, museums, manufacturing, green-houses, farm animal shelters, and many more.

2

Section Z06 TeEC 7521 n9 3a Tmperature + IiDMkaity Sensor Specifications Relative Humidity (RH)

Accuracy/Range: +/-2% for 10 to 90%;

+/-3% for 5 to 10% and 90 to 95%;

+/-4% for 0 to 5% and 95 to 100%

Non-linearity: +/-3%

Hysteresis: +/-1%RH Response Time: 8 seconds, tau 63%

Repeatability: +/-0.1%

Resolution: 0.1%, 12 bit Temperature (T)

Accuracy/Range*

Wand Probe: +/-0.50C (+/-_IF) for 50 to 450C (41° to 113°F); +/-0.5 to 10C

(+/-10 to 2°F) for 00 to 50C and 450 to 700C (320 to 41OF and 1130 to 158°F)

Industrial Probe: +/-0.50C (+/--IF) for 50 to 450C (41 to 113°F); +/-0.50 to 1.50C

(+/-10 to 2.7 0F) for -40 0 to' 5C and 450 to 1240C (-400 to 41OF and 1130 to 2550F)

• Note: extended temperature range is for Ind. probe only, the iServer's operating temperature is 0 to 700C Response Time: 5 to 30 seconds, tau 63%

Repeatability: +/-0.10C Resolution: 0.1°C, 14 bit Probe Physical Dimensions Wand Probe iTHP-W Probe length: 019 mm x 198 mm (0.75" x 7.8")

Cable length 152mm (6") with DB9 Connector Cable operating temp: 00C to 800C (320F to 1760F)

Industrial Probe iTHP-5, iTHP-2:

Probe length: 016mm x 137mm or 51mm (0.63" x 5" or 2")

Housing material: SS316 Cable length 3m (10') or 0.9m (3')

Cable operating temperature:

-400C to 125°C (-40°F to 2570 F) iServer Specifications Interfaces Ethernet (RJ45): Fixed or auto-negotiating 10/1 OOBASE-T, Auto MDI/MDIX: iTHX-SD; 1 OBASE-T: iTHX-W, iTHX-2 Sensor: Digital 4-wire (DB-9):

iTHX-W, iTHX-SD; removable 8 position screw terminals: iTHX-2 Protocols TCP, UDP, SNMP, SMTP, NTP, ARP, ICMP, DHCP, DNS, HTTP, and Telnet: iTHX-SD; TCP, UDP, ARP, ICMP, DHCP, DNS, HTTP, and Telnet: iTHX-W, iTHX-2 LCD Display (iTHX-SD) 16 Digits 6mm (0.23")

SD Flash Memory Card (iTHX-SD) 2GB card: 8 months of data storage at 1 second recording intervals or 7 years at 10 second intervals Relay Outputs (iTHX-SD)

Two Relays 1.5A @ 30 Vdc I

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Dewpoint 11.0 C Alarm Relayl ON Alarm Relay2 OFF Recording ON ee~rhr2 IS..ned.

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Readings on iTHX-SD Software OPC Server; macro for datalogging in Excel program; compatible with Windows operating systems iTHX-W and iTHX-2 Configuration Environmental Operating Temperature:

Unit: 0 to 700C (32 to 1580F)

Battery: -20 to 550C (-4 to 131 OF) ac Adapter: 0 to 400C (32 to 104'F)

Storage Temperature:

-40 to 850C (-40 to 1850F)

Power Input: 9 tol2 Vdc: iTHX-W, iTHX-SD; 10 to 32 Vdc: iTHX-2 Safety Qualified ac power adapter:

Nominal Output: 9 Vdc @ 0.5A Input: 100 to 240 Vac, 50/60Hz included: iTHX-W, iTHX-SD Switching Power Supply sold separately: iTHX-2 Battery: 9Vdc, Alkaline iTHX-SD Packaging Material: Steel metal case with wall mount bracket: iTHX-SD; Valox 364 PBT case with wall mount bracket:

iTHX-W; Polycarbonate case with DIN Rail mount: iTHX-2 L*

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In compliance with IS09001:2000, ISO10012-1.1992(E),

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Description Price iTHX-SD iServer MicroServer'" for Temp + Humidity and Dew-point, LCD Display, 2GB SD Flash Memory Card, 2 Relay Alarm, Battery Back-up 395 iTHX-W iServer MicroServer'" for Temperature + Humidity and Dew Point 295

• Standard 203 mm (8") Wand Probe, Cable 152 mm (6") with DB9 Connector. No Entry required N/C

-2 Industrial 51 mm (2") Probe, Cable 0.9 m (3 ft) with DB9 Connector. Substitution for Wand Probe 15

-5 Industrial 137 mm (5") Probe, Cable 3 m (10 ft) with DB9 Connector. Substitution for Wand Probe 25 Accessories iTHP-W-6 Replacement 203mm (8") Wand Probe, Cable 152mm (6") with DB9 Connector 100 iTHP-2-DB9 Industrial 51 mm (2") Probe, Cable 0.9 m (3 ft) with DB9 Connector"1 115 iTHP-5-D89 Industrial 137 mm (5") Probe, Cable 3 m (10 ft) with DB9 Connector"1 125 DB9-Y DB9 "Y" Connector Adapter for 2 Probes with DB9 Connector 25 DB9-CA-3 Extension Cable, 0.9 m (3.ft) with DB9 Connector 15 Ordering Examples for iTHX-SD with LCD display, SD card, 2 relay alarm, battery back-up and wand probe: iTHX-SD = $395.

For dual channel iTHX-2 with additional industrial 5" probe and 10' cable:

iTHX-2 + iTHP-5 + iDRN-PS-1000. $295 + 125 + 150 = $570.

For Calibrated Replacement Probe, with Certificate: iTHP-W-6-CAL-3-HU.

-1 Other lengths of cable (up to 40 ft) are available, please contact our Sales Model No. Description Price iTHX-2 iServer MicroServer'" for Temperature + Humidity and Dew Point 295

• Standard Industrial Probe 137mm (5"), Cable 3 m (10 ft), Stripped Wire Leads. No Entry required N/C

-2 Industrial Probe 51mm (2"), Cable 0.9 m (3 ft) with Stripped Wire Leads. Substitution for 5" Probe N/C Accessories iTHP-2 Industrial Probe 51 mm (2"), Cable 0.9 m (3 ft) with Stripped Wire Leads. 1 115 iTHP-5 Industrial Probe 137 mm (5"), Cable 3 m (10 ft) with Stripped Wire Leads. "1 125 iDRN-PS-1000 Power Supply (switching), 95 to.240 Vac input, 24 Vdc output @ 850 mA (powers up to 7 units) 150 RAIL-35-2 2 m (6.5 ft) section of 35mm DIN rail 15 Common Accessories Price iP-PC Polyethylene Probe Cap, for wet environments N/C iP-SC Porous Stainless Steel Probe Cap, 5um porosity, for dusty and pressurized (< 35 psi) environments 25 CAL-3-HU NIST Traceable Calibration Certificate. Three (3)

Humidity Points of 25%, 50%, 75%, one temp-erature 25'C, for new units 150 CAL-3-DUAL Same as CAL-3-HU, for new units with 2 probes 175 CT485B-CAL-KIT Calibration Kit, 33% and 75% RH Standards 75

$100 + 50 = $150.

Department.

• Volume discounts are available.

4

Section Z07 EC 75219 Page 1 of 13 (j)

TECHNICAL GUIDELINES Prepared by the International Concrete Repair Institute March 2004 Guide to Using In-Situ Tensile Pull.Off Tests to Evaluate Bond of Concrete Surface Materials Guideline No. 03739 Copyright © 2004 International Concrete Repair Institute All rights reserved.

International Concrete Repair Institute 3166 S. River Road, Suite 132, Des Plaines, IL 60018 Phone: 847-827-0830 Fax: 847-827-0832 Web: www.icri.org E-mail: info@icri.org 0

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% CB ONCRETE RPAIR EC 75219 Page 2 of 13 About ICRI Guidelines The International Concrete Repair Institute (ICRI) was founded to improve the durability of concrete repair and enhance its value for structure owners. The identification, development, andpromotion of the most promising methods and materials are primary vehicles for accelerating advances in repair technology. Working through a variety offorums, ICRI members have the opportunity to address these issues and to directly contribute to improving the practice of concrete repair A principal component of this effort is to make carefully selected information on important repair subjects readily accessible to decision makers. During the past several decades, much has been reported in the literature on concrete repair methods and materials as they have been developed and refined. Nevertheless, it has been difficult tofindcritically reviewed information on the state of the art condensed into easy-to-use formats.

To that end, ICRI guidelines are prepared by sanctioned task groups and approved by the ICRI Technical Activities Committee. Each guideline is designed to address aspecitic area ofpractice recognized as essential to the achievement of durable repairs. All ICRI guideline documents are subject to continual review by the membership and may. be revised.as approved by the Technical Activities Committee.

Technical Activities Committee Rick Edelson, Chair David Akers Paul Carter Bruce Collins Bud Earley Garth Fallis Tim Gillespie Fred Goodwin Scott Greenhaus Bob Johnson Ken Lozen Kevin Michols Joe Solomon Producers of this Guideline Task Group Members Ken Lozen, Chair Paul Carter Robert Gaul Peter Kolf Kevin Michols Jeff Travis Evaluation Committee Larry Olson, Chair Paul Carter Kevin Michols Rick Edelson Michael Moran Robert Gracey Larry Mrazek Peter Kolf Oon-Soo Ooi Peter Lipphardt Claus Petersen Ken Lozen Steve Stokowski Tracy Marcotte Matthew Thomas Jim McDonald Jeff Travis Contributors Robert Gulyas Alex Vaysburg Acknowledgments The task group wishes to acknowledge the following original task group members for their initial efforts in preparing this document:

Neal Kanaya Tom Kline Keith Pashina Synopsis This guide is intended to provide a recommended method of evaluating the tensile bond of cementitious and polymer concrete surface repairs using in-situ drilled core tensile pull-off tests. This guide out-lines equipment and material requirements, the test procedure, reporting, and acceptance criteria.

Appendixes discuss the importance of bond to successful surface repairs and summarize factors affecting bond tests.

Keywords Acceptance criteria, bond, bond failure, cohesive failure, composite system, concrete substrate, failure mode, pull-off strength, pull-off test, repair composite, surface repair, tensile bond, tensile load, trial repair.

I 0

0 This document is intended as a voluntary guideline for the owner, design profes-sional, and concrete repair contractor. It is not intended to relieve the professional engineer or designer of any responsibility for the specification of concrete repair methods, materials, or practices. While we believe the information contained herein represents the proper means to achieve quality results, the International Concrete Repair Institute must disclaim any liability or responsibility to those who may choose to rely on all or any part of this guideline.

03739 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS

Section Z07 EC 75219 Page 3 of 13 INTERNATIONAL C ONCRETE REPAIR I N S T I T U T E if Contents

1.0 Purpose and Scope

1 2.0 Overview of Test M ethod................................................................................................................

1 3.0 Equipm ent and M aterial Requirem ents.................................................................................

1 4.0 Test Procedure.................................................................................................................................

2 4.1 Test Site Selection/Surface Preparation...............................

2 4.2 Test Specim en Preparation..................................................................................................

2 4.3 Loading and Testing.............................................................................................................

3 5.0 Test Report......................................................................................................................................

4 6.0 Acceptance Criteria.........................................................................................................................

5 6.1 Establishing Required Pull-Off Strength Prior to Repairs....................................................

5 6.2 Time and Frequency of Tests on Completed Repairs..........................................................

6 6.3 Evaluation of Test Results on Completed Repairs...............................................................

7 Appendix A: Importance of Bond to Successful Surface Repairs....................................................

8 Appendix B: Factors Affecting Bond Tests....................................................................................

10 0

C GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 03739

Section Z07 EC 75219 Scin,7E751Page 4 of 13 INTERNATIONAL

• ICRI CONCRETE REPAIR IN ST IT UT E

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1.0 Purpose and Scope This guide has been prepared to aid and assist the facility owner, concrete repair designer, contractor, and repair material manufacturer by providing a recommended method of evaluating the tensile bond of cementitious and polymer concrete surface repairs using in-situ drilled core tensile pull-off tests. Typical applications include, but are not limited to, a prepared concrete substrate, partial depth repairs, overlays, encasements, and composite systems.

The repair of concrete surfaces involves the construction of a composite system that will differ from the existing concrete substrate. The new composite system (Fig. 1) consists of the following elements:

" existing concrete substrate;

• bond interface between existing concrete substrate and repair material; and-

" repair material.

Composite System 0

this guide is responsible to determine appropriate safety and health practices prior to performance of the test, 2.0 Overview of Test Method To perform the tensile pull-off test:

" the test site and surface are prepared;

" a core bit is used to drill through the prepared concrete substrate or the repair material/existing concrete substrate composite system;

• a rigid disc is attached to the top of the drilled core with a high-strength adhesive;

" the testing device applies a perpendicular tensile load to the core through the rigid disc; and

• tensile bond strength is reported as failure load divided by cross-sectional area of the core, and type of failure mode is also identified.

3.0 Equipment and Material Requirements

" Coring Machine/Core Bit--Coring machine shall be capable of coring perpendicular to the test surface without exerting any load onto the drilled core. Core bit shall be diamond-tipped.

" Rigid Disc-Disc shall be minimum 2.0 in.

(50 mm) in diameter with adequate thickness to distribute the applied force without disc warping. For steel, a 2.0 in. (50 min) diameter disc shall be a minimum of 0.8 in. (20 mm) thick; a 3.0 in. (75 mm) diameter disc shall be a minimum of 1.2 in. (30 mm) thick. For aluminum, a 2.0 in. (50 mm) diameter disc shall be a minimum of 1.0 in. (25 mm) thick; a 3.0 in, (75 mm) diameter disc shall be a minimum of 1.5 in. (38 mm) thick. Thickness of larger-diameter discs shall be increased sufficiently to prevent disc warping. The diameter of the drilled core shall match the disc diameter.

" Adhesive-For bonding a rigid disc to the drilled core, use a paste or gel adhesive that achieves a tensile bond strength to the test surface and disc that exceeds the tensile strength of the existing concrete substrate or repair composite.

" Pull-Off Testing Device-The, minimum capacity of the device shall be at least twice the loading required to meet the acceptance L

L Repair material Bond interface Existing concrete substrate Fig. 1: Elements of a composite system The recommended test method creates a tensile stress throughout the composite system that evaluates the soundness of the existing concrete substrate prepared for repair, and/or the bond strength of the repair material, and/or the tensile strength of the repair material. The test will also identify the location of failure and quantify the failure stress of the repaired concrete composite under a tensile load. The test method may also be used to evaluate the adhesive strength of bonding agents.

The recommended method of in-situ tensile pull-off tests involves hazardous materials, equipment, and operations (for example, core drilling to avoid embedded post-tensioning tendons, electrical conduit, etc.). This guide does not address the safety issues associated with the method. The user of 0

GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 03739-1

-1, INS RNATIONAL tItI CONCRETE REPAIR 1,; I N S T I T U T E EC 75219 Page 5 of 13 criteria (refer to Section 6). Fora 2.0 in. (50 mm) diameter core, the required device typically has a capacity of at least 1500 lb (7500 N). The device shall be capable of applying a uniform force to the test specimen, which develops a stress of 5.8 +/- 2.9 psi (0.04 +/- 0.02 MPa) per s.

The device shall be capable of recording the failure stress to the nearest 10 psi (0.07 MPa).

The coupling used to connect the disc to the device should be designed to safely withstand the maximum tensile force, and to transmit the tensile force parallel to and in-line with the core axis without introducing bending, eccentricity, or rotational forces to the test specimen. The device shall be calibrated in accordance with manufacturer recommendations.

Other Equipment-Thermometer, calipers, and measuring device.

4.0 Test Procedure 4.1 Test Site Selection/

Surface Preparation 4.1.1 Test Site Selection

" Location should be sound and free of delamination/debonding; and

" Location should avoid embedded items (for example, reinforcing steel, post-tensioning tendons, electrical conduits, etc.).

4.1.2 Test Surface Preparation

" Clean to remove all surface contaminants and loose or deteriorated concrete; and

" Prepare the test surface in accordance with project requirements and equipment manufacturer recommendations. For irregular test surfaces, preparation methods must provide a surface that allows firm and uniform seating of the testing device in a proper orientation to the test specimen.

Note that some manufacturers recommend grinding or planing of concrete surfaces prior to testing. While this operation can optimize proper seating of the testing device and may be desirable for repair composites, it prevents meaningful results when testing a prepared concrete substrate (because the prepared surface has been removed).

4.1.3 Rigid Disc Attachment Refer to Paragraph 4.2.4 for attachment of rigid disc to the test surface prior to coring.

4.2 Test Specimen Preparation 4.2.1 Coring Prepared Concrete Substrate-Drill a circular cut perpendicular to the surface and into the prepared concrete substrate to a minimum depth of 1.0 in. (25 mm) or one-half the core diameter, whichever is greater. For a 2.0 in.

(50 mm) diameter core, the minimum depth shall be 1.0 in. (25 mm), and a 3.0 in. (75 mm) diameter core shall be 1.5 in. (38 mm). The core is left intact.

• Repair Composite-Drill a circular cut perpendicular to the surface, through the repair material, and into the existing substrate.

The cut should extend to a minimum depth of 1.0 in. (25 mm) or one-half the core diameter, whichever is greater, into the existing substrate.

For a 2.0 in. (50 mm) diameter core, the minimum depth into the existing substrate shall be 1.0 in. (25 mm), and a 3.0 in. (75 mim) diameter core shall be 1.5 in. (38 mm). The core is left intact.

4.2.2 Test Speciman Cleaning Remove all standing water. Clean the test surface of any debris from the drilling operation and allow to dry.

4.2.3 Rigid Disc Attachment After Coring Attach the rigid disc to the top of the drilled core using an adhesive (refer to Section 3, Equipment and Material Requirements). The surface must be clean and the disc centered over the drilled core. Cure theadhesive per the manufacturer's instructions. Do not allow the adhesive to run down the side of the drilled core into the annular ring.

If this occurs, discard the test specimen and prepare another. At temperatures below 68 'F (20 'C),

it is permitted to gently heat the disc to no more than 120 'F (50 'C) to facilitate the spreading and curing of the adhesive. Do not heat the disc/core with a direct flame. A hairdryer is often used.

Allow sufficient time for the adhesive to cure.

4.2.4 Rigid Disc Attachment Prior to Coring As an option, the rigid disc may be attached to the test surface in Paragraph 4.1 prior to coring in Paragraph 4.2, as long as coring will not adversely C)

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03739-2 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS

Section Z07 EC 75219 Page 6 of 13

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CONCRETE REPAIR

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.4 Existing concrete substrate Fig. 2: Test specimen preparation (composite system) affect or damage rigid disc installation. Refer to Paragraph 4.2.3 for attachment of the rigid disc.

Refer to Fig. 2 for schematic of test specimen preparation.

4.3 Loading and Testing Attach the pull-off testing device to the rigid disc. The reaction frame of the testing device must bear uniformly on the test surface to produce a perpendicular tensile load (that is, without eccentricity);

Apply a tensile load at a constant rate of 5.8 +/-

2.9 psi (0.04 +/- 0.02 MPa) per second to the test specimen in a direction perpendicular to the concrete surface and parallel to the axis of the drilled core (Fig. 3);

(9 Testing device Reaction frame Repair material

-Drilled core 0

Bond interface Core diameter (D)

Existing concrete substrate Fig. 3: Test setup (composite system)

GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 03739-3

Section Z07

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CONCRETE REPAIR INSTITUTE EC 75219 Page 7 of 13 Bond I nterrface j

.,*__.__Rigid

~disc

~Repair material Existing concrete substrate Failure Mode 1 Bond failure at rigid disc (100% B/C) f t

Failure Mode 2 Cohesive failure of repair material (100% B) t Failure Mode 3 Bond failure (100% A/B) f Failure Mode 4 Partial bond failure and cohesive failure of repair material (60% A/B, 40% B)

Failure Mode 5 Partial bond failure and cohesive lailure of existing concrete substrate (60% A/B, 40% A)

Failure Mode 6 Cohesive failure of existing concrete substrate (100% A)

Fig. 4: Pull-offfailure modes (composite system)

Record the failure load and the mode of the failure (Fig. 4). Record the failure mode as:

Mode 1: Adhesive bond failure of disc to the prepared substrate (without repair material) or repair material (composite system).

Mode 2: Cohesive failure within repair material.

Mode 3: Bond failure of repair material to the existing substrate.

Mode 4: Partial bond failure of repair material to the existing substrate and partial cohesive failure within the repair material.

Mode 5: Partial bond failure of repair material to the existing substrate and partial cohesive failure within the existing substrate.

0 Mode 6: Cohesive failure within the existing substrate.

" Calculate area of the drilled core by measuring the diameter of the core along two perpen-dicular axes to the nearest 0.01 in. (0.25 mm) and averaging the two readings; and

• Calculate bond or tensile strength in psi (MPa) as tensile load/area of drilled core (Fig. 5).

5.0 Test Report The test report should contain the following:

• project information;

" equipment and materials used, including type ofpull-offtcsting device and type/size of core/

rigid disc;

• age and conditions of existing substrate and repair material;

" location of test, weather conditions, and concrete surface temperatures;

• failure load or stress to the nearest 10 psi (0.07 MPa);

" calculated bond or tensile strength to the nearest 5 psi (0.035 MPa); and

• mode of failure.

Refer to Fig. 6 for sample test report.

TBS = Tensile Bond Strength P = Pull-off force at failure = 1150 lb.

D = Diameter of core = 3.0 in.

A = Area of core A = _LD-.. 3.14 x (30) = 7.06 in.

4 4 TBS 1150 = 165 psi A-A-

7.06 -

0 Fig. 5: Sample tensile bond strength calculation 03739-4 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS

Section Z07 EC 75219 Page 8 of 13 1AN1INTER NATIONAL WKCI N

NCONCRETE REPAIR TIN ITi T U T E In-Situ Tensile Pull-Off Test Results Project no.:

Weather:

Project name: _

Project address:

Structure type:

Owner:

Temperature:

Testing device:

Core/rigid disc size:

Surface preparation method:

Engineer:

Repair material type:

Age of repair material:

Contractor:

Applied Core Core Tensile Date Test Gage force dia.

area bond Failure Remarks no.

reading (P)

(D)

(A) strength mode no.____ readin__p)

O)_(A (P/A)

Fig. 6. Sample test report (9

6.0 Acceptance Criteria 6.1 Establishing Required Pull-Off Strength Prior to Repairs 6.1.1 Trial Repairs 6.1.1.1 Time and Frequency of Tests Significant variance exists between the abilities of concretes of different composition and quality to resist pull-off stresses. It is recommended that trial repairs be made to evaluate the capacity of the existing concrete substrate and the repair materials to resist pull-off stresses. If the trials demonstrate that the strength of the existing concrete substrate and repair are not adequate, the advis-ability of making the repair should be re-evaluated.

If possible, the amount and location of tests should be shown on the repair drawings or described in project specifications whenever pull-off testing is used as a basis for assessing surface repairs.

Trial sample repairs should be undertaken for each type of designated repair far enough before the related work is scheduled to allow curing of the repair materials and completion of evaluation tests. Pull-off tests should not be performed until at least 3 days after repairplacement for polymer-based materials and 7 days or more after repair placement for cementitious materials. Pull-off tests may be performed at earlier ages if the design strength of the repair material has been met.

Testing at later ages may be desired for slower strength gain repair materials and when curing occurs in cold weather, but not later than 28 days after repair placement. Pull-off tests should be performed at ages consistent with anticipated project schedule requirements. Trial sample repairs should be carried out using the same concrete removal and surface preparation methods, and the same material formulation and application methods as those to be used in the 0

GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 03739-5

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,CONCRETE REPAIR icy~

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EC 75219 Page 9 of 13 C0 work. New trial sample repairs should be carried out if any changes in materials and equipment occur during the course of the work.

Trial sample repair areas should be chosen, to the extent reasonably possible, to encompass the.

majority of the positions and orientations of the surfaces to be repaired.

During the trial repairs, perform testing of a minimum of three test specimens for each trial repair area.

6.1.1.2 Required Pull-Off Strength Based on Trials Requirements for the pull-off strength established by the trials should be based on achieving an average of 90% of the average trial speciman test results. Perform an additional speciman test to replace any specimen test with a result less than 75% of the average pull-off strength of the trial specimen test results.

The required pull-off strength should not exceed the tensile strength of the existing substrate or repair material, whichever is lower.

6.1.1.3 Revision of Pull-Off Strength Requirements If unexpected job conditions are encountered, including lower/higher strength of the existing concrete substrate to be repaired, acceptance criteria may have to be adjusted to meet specific project conditions.

6.1.2 If Trial Repairs are not Possible The requirement for trial repairs depends, to a certain extent, on the size of the project and the time available prior to repairs. If trial repairs are not possible, the following guidelines based on field experience may be helpful.

Structural performance of bonded repairs generally relies on the transfer of shear stresses across bond lines. These stresses may result fr-om shrinkage of the repair material with respect to the existing substrate, differential thermal cycling between the repair and existing substrate, external loads applied to a structure, or other phenomena. While limited test data are available, there is no well-established correlation between tensile bond capacity and shear capacity of a bond line. Further, accurate calculation of bond line stresses under various loading conditions can be complex if all factors, including shrinkage and thermal volume changes, are considered. It should be recognized, therefore, that calculation of aprecise tensile bond value necessary to satisfy structural requirements is not realistic. Consequently, acceptance criteria is typically developed based on an approximate calculation of shear demand, th 'e assumption that shear capacity of the bond line will exceed tensile capacity, knowledge of bond values known to be achievable with specified methods and materials, and knowledge of performance of other sinilar repairs.

Experience demonstrates that bond strengths of 250 psi or greater can be achieved with available surface preparation and repair techniques in moderate to good quality concrete substrate materials. Test values of less than 250 psi that fail consistently within the existing concrete substrate may be an indication of an inferior or low-strength concrete substrate.

Many specifiers use an acceptance criteria lower than 250 psi in recognition of surface preparation techniques that may be restricted in some manner, a repair application for which higher bond strength is perceived to be unnecessary, and possible data inaccuracies related to bond test procedures or equipment, etc.

Legitimate test values (that is, those for which a high confidence in test methods and equipment is present) lower than 175 psi that fail at the bond line or superficially within the existing concrete substrate may indicate a partially damaged or contaminated bond surface. Where high bond strength is judged to be critical, investi-gation of the bond surface, assessment of exist-ing concrete substrate strength, or selection of alternative surface preparation techniques should be performed. For repairs in which bond strength is perceived to be less critical, some specifiers allow acceptance of bond strengths for cementitious materials as low as 100 psi. A minimum pull-off strength of 200 psi is generally required for polymer materials.

6.2 Time and Frequency of Tests on Completed, Repairs Pull-off test should not be performed until at least 3 days after repair placement for polymer-based materials and at least 7 days or more after repair replacement for cementitious materials. Pull-off tests may be performed at earlier ages if the design strength of the repair material has been met. Testing at later ages may be desired for slower strength gain repair materials and when curing occurs in cold weather. 'Pull-o ff tests should be performed at ages consistent with trial repair testing.

01 U

03739-6 03739-IGUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS

Section Z07 EC 75219 Section Z07 EC 75219 flisLCONCRETE REPAIR IN S T IT U T E

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(9 For overlays and large repair areas, a minimum of three individual specimen tests should be performed for each 500.0 ft2 of repair. For smaller repair areas, a lesser frequency of testing may be more appropriate; however, a minimum of three specimen tests should be performed on the project. Additional guidance regarding frequency of sampling can be found in ASTM E 122, "Standard Practice for Calculating Sample Size to Estimate, With a Specified Tolerable Error, the Average for a Characteristic of a Lot or Process." Test surfaces should be selected at random. Refer to ASTM D 3665, "Standard Practice for Random Sampling of Construction Materials," for guidance regarding random sampling criteria. At -least one specimen test should be performed near a randomly selected perimeter edge or saw-cut joint.

6.3 Evaluation of Test Results on Completed Repairs The acceptance criteria should be interpreted based on the analysis of failure modes (Fig. 4).

6.3.1 Acceptance of Test Results For all modes of failure, accept pull-off test results if "For criteria developed by trial repairs:

Average Strength: Average pull-off strength of the specimens is above the required pull-off strength (90% of average trial specimen test value).

Minimum Strength: No specimen tests below 75% of the average trial specimen test value.

"For criteria developed without trial repairs:

Average Strength: Average pull-off strength of the specimens is above the required pull-off strength.

Minimum Strength: No specimen tests below 75% of the required. strength.

6.3.2 Test Results Below Minimum Strength Requirements For tests that fail to meet minimum strength requirements:.

test specimen may be faulty if the adhesive fails, adhesive does not completely fill the interface between the disc and the test surface, the disc is off-center, or the disc is not aligned in a plane perpendicular to the axis of the core;

" check for proper disc adhesion, positioning, and alignment;

" check alignment of testing device to assure that load is being applied parallel to axis of the core and axis of core is perpendicular to the test surface;

" retest specimens that did not meet minimum requirements;

" use values of acceptable specimens from original test with values derived from retest to detcrmine adjusted average; and

" accept if adjusted average is above required pull-off strength and no specimen tests below the minimum required strength.

6.3.3 Test Results That Consistantly Do Not Meet Acceptance Criteria When test results consistently fail to meet the acceptance criteria, a re-evaluation of project conditions should be performed. This assessment may include the re-evaluation of the required pull-off strength (average/minimum strength criteria), failure modes, repair/substrate materials, construction procedures, etc.

0 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 33-03739-7

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.INSTTUT EC 75219 Page 11 of 13 Appendix A Importance of Bond to Successful Surface Repairs The Composite System Concrete surface repairs and overlays are composite systems. In composite systems, the bond between the individual components is critical for overall viability. The durability of the bond in such systems can be defined as a lasting, interfacial coexistence of new and existing phases. Assuming the properties of the components are good, any improvement of the bond will improve the properties of the composite system.

A Good and Lasting Bond Achieving an adequate lasting bond between repair materials and existing concrete substrate is a critical requirement for durable surface repairs and overlays. The basic requirements for good bond are simple:

" absence of weak layers or contamination at the interface; and

" intimate contact between repair material and existing concrete substrate.

The bond at the interface between the repair material and existing concrete substrate, or phases, is likely to be subject to considerable stresses from internal forces (volume changes, freezing-and-thawing cycles, etc.), and external forces (force of gravity, impact, vibration, overall structural response, etc.). The stress conditions that develop at the bond line will vary considerably, depending on the type, use, and exposure of the structure. For example, the bond on a bridge deck overlay may be subject to shear stress in conjunction with tensile or compressive stress induced by shrinkage or thermal effects, and to compression and shear from service loads.

It is essential that the repair or overlay materials achieve a strong bond to the existing concrete substrate and that subsequent stresses not be severe enough to cause debonding. Repairs that have bond lines in direct tension have the greatest dependence on chemical bonding (adhesion). Repairs that are subject to shear stresses at the bond line are capable of stress resistance not only by chemical bonding mechanisms, but also by mechanical bonding (that is, aggregate interlock) mechanisms, which add greatly to shear bond capacity.

The key requirement of a successful repair is an adequate bond between the repair material and existing concrete substrate, which remains intact throughout its service life. At the present time, practical answers to the problems of bond may depend only on a short-term bond testing rather than long-term performance. An initially achieved adequate bond is only an indication of conformance with the specified parameters. There is no well-defined relationship between initial bond strength and the longevity of a repair. Longevity is influenced by many factors, including substrate surface preparation and texture, shrinkage of the repair material, and service conditions.

Factors Affecting Bond Adherence between the repair material and existing concrete substrate in a composite system is a case of adhesion between solids, formed as a result of the setting and hardening of a semi-liquid substance (the repair material) placed on the surface of a second substance in solid state (the existing concrete substrate). Being semi-liquid, repair materials flow into the existing substrate surface irregularities of a solid, coming into intimate contact with the substrate and, as a result, interacting with its molecular forces. Factors that influence the formation of a bond and the degree of adhesion include: existing substrate properties, repair material properties, surface preparation methods, concrete placement and curing methods, and environmental exposure.

Differing Concrete Surfaces The chemical and physical properties of existing concrete surfaces are complex, and a great deal of variability in these properties may occur through-out a repair or overlay area. Consideration of these properties is necessary to develop a recognition of methods and procedures that promote the development of good bond with repair materials.

Concrete surfaces are dissimilar in many properties, which include, but are not limited to:

" porosity;

• absorption;

• roughness/texture;

" degree of microcracking ("bruised" layer); and

" hardness.

Concrete surfaces can change with time as a result of:

• external mechanical forces such as those associated with concrete removal and surface preparation operations; N

Cj)

U 03739-8 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS

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Section Z07 EC 75219

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• interaction with the exterior environment. For instance, carbonation causes physical changes in porosity, water absorption, and hardness; and cracking can result from shrinkage and thermal effects; and

. interaction with the interior environment. For instance, moisture and chloride ingress causes electrochemical changes that may lead to corrosion of reinforcing steel.

A properly prepared concrete substrate facilitates the development of sufficient bond between the existing concrete substrate and repair material (refer to the ICRI Guideline No. 03732, "Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays," and ICRI GuidelineNo. 03730, "Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion").

The most important characteristics of the prepared concrete surface with respect to achieving good bond are its roughness, soundness (that is, absence of contaminants and damaged paste or aggregate), cleanliness, and moisture condition prior to the application of the repair material. The most important factors during and after repair material placement are the selection of a suitable repair material and achieving proper installation, proper consolidation, and adequate curing. Each of these factors is mainly dependent on work-manship. The primary factor outside the control of a repair program is the quality of the existing concrete substrate intended to receive the repair, aside from issues related to damage that may be caused by concrete removals and surface preparation. Tensile pull-off testing has been found to be an effective tool in evaluating the integrity of the existing concrete substrate and the quality of workmanship exercised in the execution of a repair.

(

References ASTM D 3665, "Standard Practice for Random Sampling of Construction Materials,"ASTM Book of Standards, V. 04.03.

ASTM E 122, "Standard Practice for Calcu-lating Sample Size to Estimate, With a Specified Tolerable Error, the Average for a Characteristic of a Lot or Process," ASTM Book of Standards, V. 14.02.

Austin, S.; Robins, P.; and Youguang, P., 1995, "Tensile Bond Testing of Concrete Repairs,"

Materials and Structures, V. 28, pp. 249-259.

British Standard BS 1881, 1992, "Recommen-dations for the Assessment of Concrete Strength by Near-to-Surface Tests," Part 207.

Bungey, J. H., and Mandandoust, R., 1992, "Influencing Pull-Off Tests in Concrete,"

Magazine of Concrete Research, V. 44, No. 158, pp. 21-30.

Canadian StandardAssociation CSAA23.2-6B, "Method of Test to Determine Adhesion by Tensile Load."

Collins, F. G., and Roper, H., 1989, "Evaluation of Concrete Spall Repairs by Pull-Out Test,"

Materials and Structures, RILEM, V. 22, pp. 280-286.

Hindo, K. R., 1990, "In-Place Bond Testing and Surface Preparation of Concrete," Concrete International, V. 12, No. 4, Apr., pp. 46-48.

Li, S.; Frantz, C.; and Stephens, J. E., 1997, "Application of Pull-Off Test to Assess the Durability of Bond between New and Old Concrete Subjected to Deicer Salts," Innovations in Non-Destructive Testing of Concrete, SP_-168, S. Pessiki and L. Olson, eds., American Concrete Institute, Farmington Hills, Mich., pp. 267-294.

Long, A. E., and Murray, A., 1984, "The Pull-Off Partially Destructive Test for Concrete,"

In-Situ/Nondestructive Testing of Concrete, SP-82, V M. Malhotra, ed;, American Concrete Institute, Farmington Hills, Mich., pp. 327-350.

Mathey, R. G., and Knab, L. I., 1991, "Uniaxial Tensile Test to Measure the Bond of In-Situ Concrete Overlays," NISTIR 4648.

McLeish, A., 1993, "Standard Tests for Repair Materials and Coatings for Concrete-Part I:

Pull-Off Tests," Technical Note: 139, CIRIA.

Petersen, C. G., 1990, "New Bond Testing Method Developed," Concrete Repair Bulletin, V. 3, No. 5, Sept.-Oct., pp. 6-8.

U.S. Army Corps of Engineers, 1999, "An Evaluation of Equipment and Procedures for Tensile Bond Testing of Concrete Repairs,"

Technical Report REMR-CS-61, June.

Q GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS 03739-9

I Section Z07 (0

INTERNATIONAL CONCRETE REPAIR INST IT UT E EC 75219 Page 13 of 13 Appendix B Factors Affecting Bond Tests Several test methods have been proposed to evaluate bond properties of composite repair and overlay systems. These include the following:

1. Tensile bond tests

" Canadian Standard Association CSA A23.2-6B, "Method of Test to Determine Adhesion by Tensile Load;" and

" British Standard BS 1881, 1992, "Recom-mendations for the Assessment of Concrete Strength by Near-to-Surface Tests," Part 207.

2. Slant-shear tests

" BS 6319, Testing of Resin Composites for Use in Construction, Part 4: "Method of Measurement of Bond Strength (Slant-Shear Method)," British Standards Institute, London, 1984.

" Kriegh, J. D., 1976, "Arizona Slant Shear Test: A Method to Determine Epoxy Bond Strength," ACI JouRNAL, Proceedings V. 73, No. 7, July, pp. 372-373.

3. Twist-off shear test

• Naderi, M.; Cleveland, D. J.; and Long, A. E.,

1986, "Bond Strength of Patch Repair Mortars for Concrete," Proceedings of the RMEM International Symposium on Adhesion between Polymers and Concrete, Chapman & Hall, London, pp. 7 07-71 8.

However, the most widely used field test has been the "pipe cap" pull-off test described in ACI 503R Appendix A and refinements of that test, such as the State of Virginia test method VTM-92 and commercial adaptations.

Pull-offtensile bond tests are gaining inpopularity because of their relative simplicity and ability to meet most of the requirements for in-situ bond evaluation of concrete surface repairs.

The most important aspects of the tensile pull-off (bond) test are:

• load rate (that is, both the rate of load application and the uniformity of the rate of load application);

" load alignment (that is, axial with a core specimen to be tested and perpendicular to the surface to be tested);

• coring depth; and

• core/rigid disc size and rigid disc stiffness.

LoadRate: Load must be applied at a uniform rate. Abrupt starts and stops, such as those that occur by a series of discrete hand cranks in some test apparatus, are undesirable. Further, load application should be at a moderate rate that does not impart any impact effects nor creep effects.

Load Alignment: The objective of putting a bond plane into a uniform tensile stress state has been a challenge where the principal concern has been to minimize load eccentricity. Load eccentricity in a pull-off test depends on the normality of the core drilling (relative to the substrate) and accuracy in positioning the rigid disc on top of the core. For instance, if the eccentricity induced is 0.06 in. (1.5 mm) in a depth of 2.0 in. (50 mm), corresponding to an angle of 1.7 degrees, this leads to an increase in maximum stress at the core periphery of 20%

(Austin, Robins, and Youguang 1995).

Coring Depth: Studies have shown (U.S. Army Corps of Engineers 1999) that a shallow coring depth beyond the bond line into the existing concrete substrate can cause significant stress concentrations at the periphery of the test specimen near the bond line. The greater the coring depth, the lesser impact on the test results. Based on available data, a minimum depth of 1.0 in.

(25 mm) into the existing substrate (beyond the bond line) is recommended for 2.0 in. (50 mm) diameter cores, and 1.5 in. (38 ram) for 3.0 in.

(75 mm) diameter cores.

Core/RigidDisc Size andRigidDisc Stiffness:

In general, larger-diameter cores and discs provide a more representative sampling. While 2 in, (50 mm) diameter cores have been widely used for many years, some prefer larger, up to 3 in.

(75 mm) diameter, cores. Larger core/rigid disc size may be more appropriate for thicker repairs and/or testing of concrete with larger size aggregates. In all cases, it is imperative that the rigid disc adhered to the surface of the test specimen have sufficient rigidity to distribute the applied load uniformly across the surface of the test specimen.

These factors must be controlled to minimize the variability of the test results and the influence of stress concentrations. Controlling these important factors can be challenging in field conditions. In particular, proper selection of a commercially available testing device has a significant impact of test results (U.S. Army Corps of Engineers 1999).

C) 03739-10 GUIDE TO USING IN-SITU TENSILE PULL-OFF TESTS TO EVALUATE BOND OF CONCRETE SURFACE MATERIALS