ML20125C175
| ML20125C175 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 12/19/1979 |
| From: | Trammell C Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TAC-12369, NUDOCS 8001040563 | |
| Download: ML20125C175 (75) | |
Text
.
f CECEYEER 1 i M' Meeting Summary for Trojan Docket Files Mr. Jack W. Lentsch, Manager NRC POR Local POR Generation Licensing and Analysis Portland General Electric Company ORBI Reading 121 S.W. Salmon Street NRR Readin9 Portland, Oregon 97204 H. Denton 1
E. Case Columbia County Courthouse O. Eisenhut Law Library, Circuit Court Room B. Grimes St. Helens, Oregon 97501 R. Vollmer-J. Miller L. Shao Director, Oregon Department of Energy W. Gammill Labor and Industries Building, Room 111 G. Zech Salem, Oregon 97310 A. Schwencer D. Ziemann Dr. Hugh 0. Paxton 1220 41st Street P. Check G. Lainas Los Alamos, New Mexico 87544
- 0. Davis Michael Malmrose B. Grimes T. J. Carter V. S. Nuclear Regulatory Commission T. Ippolita Trojan Nuclear Plant
- 0. Crutchfield P. O. Box 0 R. Reid Rainier, Oregon 97048 V. Noonan.
G. Knighton Dr. Kenneth A. McCollom, ean D. Brinkman Division of Engineering, P. T. Kuo Architecture and Technology Project Manager Oklahoma State University Stillwater, Oklahoma 74074 OELO 050 (3 )
Mr. Eugene Resolie er h Kreutzer Coalition for Safe Power 215 S.:.
9th Avenue y"8'Y'ACRS(16)
Portland, Oregon 97214
'M;~ Miller, ASLB -
Richard M. Sandvik, Esquire William Kinsey, Esquire Frank W. Ostrander, Jr.
1002 N.E. Holladay Counsel for Oregon Dept. of Portland, Oregon 97232 Energy 500 Pacific Building R'onald W. Johnson, Esquire 520 S.W. Yamhill Corperate Attorney Pocland, Oregon 97204 Portland General Electric Company 121 S.W. Salmon Street Maurice Axelrad, Escuire pnetiand. Oregon 97204 Lowenstein, Newman, Reis, Axelrad and Toll Suite 1214 1025 Connecticut a. venue, N.W.
Wasnington, D. C.
20036 u.s. Nina Bell 720 S.E. 26th Street Portl anc, Oregon 97214 90002075
s f
E(pa acog[o, UNITED STATES
}* ) s-y i
NUCLEAR REGULATORY COMMISSION E
WASHINGTON, D. C. 20555 r,.' g o
cr: m t: 1, %
Docket No. 50-344 LICENSEE: Portland General Electric Company (PGE)
FACILITY: Trojan Nuclear Plant
SUMMARY
OF MEETING HELD ON DECMEBER 5-6, 1979, WITH PORTLAND GENERAL ELECTRIC COMPANY (PGE) AND BECHTEL TO DISCUSS LER 79-15 (MASONRY BLOCK WALL AND SUPPORT REACTION PROBLEM)
On December 5 and 6, 1979, the NRC staff met with representatives of PGE and Bechtel to discuss Licensee Event Report 79-15 wherein certain problems with masonry block walls and support reactions of equipment / piping attached thereto were identified. A list of attendees is attached (Attachment 1).
The material discussed consisted of Supplement 2 to LER 79-15, which was received the day before the meeting. This supplement is attached (Attachment 2).
PGE explained that this final supplement took a relatively long time to complete since all piping loads were considered in the reevaluation - non-seismic category 1 piping as well as seismic category 1 piping *.
PGE stated that all necessary through-bolting and modifications of pipe supports should be completed by about December 15, 1979.
At the conclusion of the meeting, we stated that the information presented in LER 79-15 Supplement No. 2 was not sufficient to enable us to reach a safety conclusion with respect to PGE's corrective action, and therefore requested that PGE provide the following additional information:
l 1.
For the governing load combination (0BE), provide the stress state 1
at the interface for representative walls. Consider in-plane as well as out-of-plane loading. Three composite and three block walls i
should be selected, based on highest support loads and highest gross loads.
Include interstory displacement effects.
- Except for small piping and equipment loads.
90002076
t Meeting Summary CE E.EER l i "*
2.
Provide the basis for the assumed stress cone distribution for anchor bolts.
3.
Discuss QA verification of construction to substantiate credit for special inspection. Conduct additional mortar joint tests.
4.
Provide additional data on shear transfer on mortar joints to substantiate the 18 psi allowable (Mackintosh data).
5.
Provide the maximum force transmitted on a block from a single anchor.
Provide the maximum crack size in mortar joints from out-of-plane bending (also from in-plane loading).
In addition, PGE was requested to conduct these confirmatory tests (acceptable to do during operation):
1.
Additional cores (12") of composite walls should be taken (up to a total of 25). The samples should be taken from representative walls of various thicknesses and at different elevations.
2.
A model test of a typical support in a block wall should be conducted.
PGE indicated that they expected that they would be able to provide a response to the above 5 infonnation requests in about one week. We told PGE we would need a few days at least to review their response before being able to finalize our conclusions regarding the wall / support problem.
The limited remaining time was devoted to a discussion and further clarifi-cation of the NRC structural questions of September 14, 20 and October 2, 1979, regarding Phase II of the Control Building proceeding.
~;
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( f C. M. Trammell, Project Manager Operating Reactors Branch #1 Division of Operating Reactors Attachments:
1.
List of Attendees 2.
Supplement 2 to LER 79-15 90002077 i
(
l
i 1
Attachrnent 1 LIST OF ATTENDEES TROJAN WALL / SUPPORT PROBLEM DECEMBER 5, 1979 Name Organization C. Trammell NRC 4
V. Noonan NRC K. Harring NRC l
J. Gray NRC G. Bagchi NRC B. D. Liaw NRC D. Jeng NRC D. Persinko NRC H. Wilber NRC J. Ma NRC F. Schauer NRC W. Gacmill (part time)
NRC A. Schwencer (part time)
NRC R. Johnson PGE L. Erickson PGE T. Bushrell PGE D. Broehl PGE W. White Bechtel B. Sarkar Bechtel A. Appleford Bechtel P. Chang-Lo Bechtel K. Buchert Bechtel R. Anderson Bechtel J. Hanson Wiss, Janney, Elstner and Associates A. Mackintosh M&M, Inc.
K. Kapar ENCON
- L.
- D.
Godard Oregon DOE M. Axelrad LNRA&T B. Churchill Shaw, Pittman B. Gottlieb Shaw, Pittman
- Attended briefly 90002078
.. ~.
WH
^
SUPPLEMENT NO. 2 TO LICENSEE EVENT REPORT 79-15 I.
INTRODUCTION In LER 79-15, dated November 4, 1979, the evaluations of all safety-related piping supports and restraints anchored in single wythe masonry walls and in mortared double wythe masonry walls in the Trojan Plant ( " Plant" ) were described, j
In Supplement No. 1 to.LER 79-15, dated November 19, 1979, a description of the evaluations being performed with respect to other types of structures sup;mrting safety-related piping was provided.
The purpose of this Supplement No. 2 to LER 79-15 is to provide the results of the evaluations referred to above and to provide our conclusions with respect to the occurrence identified in LER 79-15.
Bechtel Power Corporation's (Dechtel) Quality Assurance Department has investigated the cause of the occurrence iden-tified in LER 79-15 and has concluded that there appears to have been a f ailure of engineering judgment to detect the potential overstressing of walls at the Plant due to the addition of pipe loads.
Licensee has reviewed their initial report and has also reviewed the available documentation at Bechtel's offices.
On the basis of these reviews, Licensee has concluded that three factors contributed to the cause of the occurrence.
In addition to the previously described error in engineering judgment, a lack of procedures or procedural detail and insufficient design criteria (1971-72) with respect to consideration of external loads on the block walls were contributing f actors to the occurrence.
90002079
.2
e n.
Supplement No. 2 Page 2 of 10 t
Procedures are now in place at Bechtel which are intended to preclude recurrence of the problem.
Bechtel has implemented improved design verification procedures for providing assurance that the design meets the requirements specified,in the design critaris.
In addition, Bechtel procedures now require more rigorous documentation of interdisciplinary review.
The discussion below s$mmarizes our evaluations of the various types of structural elements which, with use of more conserva-tive analytical criteria than used in original design, could potentially be subject to overstress conditions, and the corrective action which has been taken.
II.
SINGLE WYTHE AND MORTARED DOUBLE WYTHE MASOlY WALLS All of the approximately 274 single wythe and mortared double wythe masonry structures in the Plant have been examined in J
our review of the potential problem identified in LER 79-15.
of these, field walkdown data revealed that approximately 33 of such walls support safety-related piping and are potentially subject to significant piping or equipment loads.1 These walls were analyzed in detail to determine whether any potential for local or global overstress condition could exist.
Attachment 1 identifies those 20 walls where corrective action to pipe supports or restraints was required and identifies the sys-tems with which the supports or restraints are associated.
1 Loads impartid by small piping ( 2" diameter and under) which do not produce thermal loads, and equipment loads less than 100 lbs., are not considered significant.
90002080 1
l
4 6
Supplement No. 2 Page 3 of 10 Corrective action consists mainly of through-bolting to mobil-ize both wythes or off-loading to adjacent structures, as.
appropriate. also provides identification of those walls where support modifications have been required which were included in the STARDYNE model Of the Control-ruel-Auxiliary Building Complex (" Complex *).
The following table summarizes the piping supports on single wythe and mortared double wythe blocP. walls in the Plant requiring corrective action according to the system involved:
Svstems Throuch-Bolt Modify Total Safety Injection 14 19 33 Res idual Heat Removal 5
23 28 Containment Spray 2
6 8
Chemical & Volume Control 8
5 13 Boron Injection 1
5 6
Spent Fuel Pool Cooling 2
7 9
Component Cooling Water 3
3 6
Containment Chilled Water 1
1
~
Steam Generator Blowdown 1
1 Service Water 6
11 17 Diesel Fuel Oil 2
2 4
TOTAL 43 83 126 All of the above modifications will be completed prior to the resumption of Plant operation.
90002081 3
9 e
e
4 a
-Supplement No. 2 Page 4 of 10 During the evaluation of the block walls of the Diesel Gener-ator Room (based on the criteria set forth in Supplement No.
1 to LER 79-15 dated November 19, 1979), it was found that certain sections of the double wythe masonry block walls supporting pipe loads on the north and south sides of the Diesel Generator Room between el. 45' and el. 69' could not satisfy the acceptance br4*avia for their hwnlout-of-plane inertia loads.
These sa11s will be strengthened by providing structural steel members to resist the out-of-plane seismic inertia and pipe support loads.
In addition to reviewing piping support and restraint capa-bility, we have reviewed the effect of hypothesized separa-tion in the mortared double-wythe reinforced concrete masonry major shear walls in the Complex as a result of either tension or shear forces.
The only such major shear walle are the following:
(1)
On line R between el. 65' and 77', and between column lines 41 and 46.
(Control Building West Wall)
(2)
On line N between el. 65' and 778, and between column lines 41 and 46.
(Control Building East Wall)
(3)
On line 46 between el. 61' and 93 ', and between column lines D and N.
(Auxiliary Building North Wall) l A separation between the wythes at the block-mortar interface of these masonry walls due to tension forces would only be 90002082 e sem p..
m esas.q
o Supplement No. 2 Page 5 of 10 possible when the interf ace is subjected to large direct ten-sion forces.
Such direct tension force could not result un-less the wall is subjected to large pipe restraint loads.
These shear walls do not support any significant pipe loads and therefore separation due to tension forces is not plausible.
The out-of-plane inertia loading on the wall would cause transverse bending, but no tension through the mortar.
- However, in order for both the wythes to act together as a monolithic.
unit to resist the out-of-plane bending, the resulting shear stress (VQ/It) must be transferred at the block-mortar inter-face.2 The foregoing major shear walls have therefore been reanalyzed for their p.ut-of-plane bending resistance capacity for the 0.25g SSE.
The following procedure was used to reanalyze the walls:
(1)
The fundamental frequency was calculated for one-way bending action of the wall with hinged end conditions at the restraining floor slab levels.
The ef fective moment of inertia of the wall section is considered to be the average of the wall gross cross-section (16-in. wythe) and the cracked section properties accounting for the vertical reinforcing steel only.
(2)
The seismic acceleration of the wall is determined from the respective floor spectra for 0.25g SSE, 8 = 5%.
2 The adequacy of placement of the mortar between the wythes is addressed in Attachment 5.
90002083
e Supplement No. 2 Page 6 of 10 (3)
The out-of-plane inertia leading, thus determined, gives the bending moment, corresponding steel stress in the vertical reinforcing steel and interface shear between the two wythes.
Table 1 lists the major shear walls and their respective stres-ses for out-of-plane se'ismic inertia loading.
The interface shear stresses are below the allowable limit set forth in of supplement 1 to LER 79-15.
The initial asump-tion that both the wythes act together as a monolithic unit to resist the seismic loads is, therefore, justifiable for these walls.
Detailed analyses of vertical shear transfer for other similarly. constructed walls have not been perfo;med.
However, based on the evaluatimme ma *"nvredTto datel i k i= not expected that tha values obtained would exceed those in Table 1.
~
III.
OTHER SUPPORT STRUCTURES
,A. Composite Walls Composite walls at the Plant are described in Attachment 3 I
to Supplement No. 1 to LER 79-15.
The criteria for detailed analyses of composite walls were provided in 7tmachment 4 to Supplement No. I to LER 79-15.
Based on ine su tests of composite walls at the Plant, the criterion for allowable prir.cipal tensile stress between 90002084
Supplement No. 2 Page 7 of 10 masonry and concrete core is now being conservatively taken as 40 psi.
( A description of the testing program and the conclusions drawn from it is provided in Attachment 3 to this Supplement.)
Load data derived from' analytical evaluations pursuant to NRC IE Bulletin 79-02 indicate that of the pipe supports or restraints utilizing expansion anchor bolts, approximately 83% have a safety factor greater than 10, approximately 10% have a safety f actor between 5 and 10, and approximately 7% have a safety f actor less than 5.
An analysis has shown that for the largest anchors used at Trojan, pure tension loading to a safety factor of 10 would subject the block-concrete interface to approxi-mately 10 psi tension; loading to a safety factor of 5 results in approximately 15 psi; and loading to a safety factor of 2 corresponds to approximately 25 poi tension.
(All supports will have a safety f actor greater than 2 prior to resumption of Plant operation, and all supports will have a safety f actor greater than 5 prior to resump-tion of Plant operation following the next refueling. )
Therefore, the direct tensile stresses induced at the j
block-concrete core interf ace due to pipe support reactions are considerably less than the conservative criteria ten-sion stress value of 40 psi.
All of the composite walls in the Plant have been con-sidered in our review of the problem identified in LER 79-15.
While wall walkdowns were in progress a review of the piping and area drawings was conducted to identify Plant areas that had the highest concentration of large 90002085 i
'Suoplement No. 2 Page 8 of 10 size safety-related piping.
Priorities for wall evalua-tions were then set with the walls in these areas to be analyzed first.
Most of these walls were surveyed by means of field walkdowns; the remainder were reviewed by means of architectural and piping drawings in order to limit radiation exposure. describes the process used in the evaluation of supports and restraints attached to these composite Walls.
A review of the walkdown packages and architectural and piping drawings indicated that approximately 64% of the walls could be eliminated from f urther consideration due to the absence of large piping or equipment that could generate significant loads.
Analyses of the remaining walls are about two-thirds complete and no thrwagh-bolting
)
or modifications have been identified.
Therefore,'on the basis of the evaluations to date, which have considered the larger safety-related piping in the Plant, we conclude that it is unlikely that analyses of the remaining walls will identify any necessary modifications.
We intend to complete the review of these other walls on an expedited basis; however, we do not consider completion of this review to be of suf ficient importance to require completion prior to resuaptior of Plant operation since we have reasonable assur: ace that no potential overstress conditions eXiSte 90002086
Supplement No.
2_
Page 9 of 10 B. Concrete Walls, Floor Slabs and Structural Steel A field survey of the entire Plant was conducted to identify those concrete walls, floor slabs and structural steel members supporting safety-related piping which could be highly loaded relative to their capacities.
The licensed Civil Engineers performing the survey identified 14 piping supports for further evaluation.
Of these, 5 were attached to structural steel and 9 were attached to concrete floor slabs.
No concrete walls were identified as being highly loaded relative to their capacities.
The survey methods are described in Attachment 4.
We have analyzed the identified structures in detail using the AISC or ACI codos, as appropriate, and the load equations from the FSAR as indicated in Attachment 4 to Supplement No. 1 to LER 79-15.
Our, analyses have indicated four of the conditions involving structural steel identified for further evaluation are adequate.
One condition re-quired a minor modification which consisted of supporting the top and bottom flange of a steel beam to provide addi-tional resistance to a torsional moment.
Che analyses of the nine conditions involving concrete floor slabs have indicated eight supports are adequate.
One support whi-k resists primarily thermal load is still be_ina_evain=~aA.
Since these support conditions were identified during a complete walkdown of all structures supporting large safety-related piping and at most two modifications are required, 90002087
9s SupDiement No. 2 Page 10 of 10 our previous judgment has been confirmed that design of these types of structural elements was adequate.
e 8
90002088 O
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' Supplement No. 2 TABLE 1 Stresses Due to Out-of-Plane Bending for Major Shear Walls in the Complex Constructed of Mortared Double Wythe Reinforced Masonry e
[
l l
l SSC = 0.25 g, S = 54 l
1 1
I l
IRebar ten-1 Mortar shear'l i Wall l Elevation l Prequency l Acceleration Isile stressi stress l
l l
I (Hz) l (g)
I fs(Ksi)
I (psi) l 1
1 1
1 I
I I
I R
l 65' - 77' l 26.1#
l 0.50 l
3.7 1
4.2 1'
l l
I l
i I
l 1
1 1
I I
l 1
1 N
l 65' - 77' 1 26.1 1
0.50 1
3.7 1
4.2 l
1 I
I I
I l
i I
I I
i 1
1 I
46 1 61' - 77' i 14.5 1
0.82 l
10.7 l
9.2 l
1 i
i i
l i
I I
I 77' - 93' !
14.5 1
0.98 l
12.8 l
11.0 l
1 I
i l
I I
I i
I i
i I
i l
90002089 1
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t F A r-T Supplement No. 2 12/3/79 3:00 PM ATTACHMENT 1 Single and Mortared Double Wythe Masonry Walls Where Corrective action to Pipe Supports or Restraints Required Page 1 of 4 Corrective Action Wall Thru-Wall Location Thickness Systen.
OK Bolt Modifv Total Aux Bldg el 5' to el 57' RHR 1
3 9
13 N/S wall betw (Col. lines) 14" SI 12 4
16 E&F Span: (betw Col. lines)
CVCS 1
1 1
3 55-56 (SA-83 Wall)
SFPC 1
4 5
1 3
CS 2
3 SW 3
1 1
SGBD Aux Bldg el 5' 2
E/W Wall near 49 14"
,J HVAC 2
Snan:
D-E SI 1
2 8
11 2
E/W Wall on 51 14" HVAC 2
Span: Approx D-E SI 3
3 1
7 1
1 N/S Wall on E 14" SI Span: Approx 49-50 1
1 N/S Wall on E 14" SI Span: Approx 47-49 E/W Wall on 55 14" RHR 1
1 4
6 2
2 Span: Approx D-E SI 90002090
e a
Page 2 of 4 Corrective Action Wall Thru-Wall Location Thickness System OK Bolt Modify Total E/W Wall on 55 14" RHR 1
1 2
4 Span: Approx G-H N/S Wall on H 14" CS 2
2 Span: 51-54 i
Aux Bldg el 17' RER 1
1 J
1 N/S Wall betw E&F 14" SI 1
Span: 49-55 SW 3
1 7
11 Aux Bldg el 25' E/W Wall on 55 14" SI 3
3 Span: near D-E I
N/S Wall near E 14" SI 1
1 Span: near 54-55
,,e i
E/W Wall on 51 14" C7CS 2
2 4
Span: F-near H Aux Bldg el 45' i
N/S Wall betw E&F 14" SI 1
1 i
Span: 50-near 61 CS 2
2 1
1 SFPC E/W Wall betw 55 & 60 14" RHR 1
1 2
Span: E to F SI 1
1 2
NW/SE Wall betw 61 E 14" CVCS 2
2 and Containment CCW 1
1 90002091
1 Page 3 of 4 Corrective Action Wall Thru-Wall Location Thickness System OK Bolt Modify Total E/W Wall on 61 14" RHR 1
1 Span: D-E SI 1
1 1
3 l
2 2
CS 2
1 SFPC 1
2 3
Aux Bldg el 61' 14" RHR 1
3 4
N/S Wall betw E&F SI 1
1 2
Span: near 60-containment CS 1
1 CVCS 1
1 2
Fuel Bldg el 61' 14" CVCS 2
2 0
4 E/W Wall South of 55 CCW l
1 an: West of B near D
( W odeled in STARDYNb)
,, ~
E7W Wall at approx 57 14" CVCS 2
2 4
Span: C - near D CCW 2
2 Turbine Building Diesel Generator A(el 45')
E/W Wall on 45 16" DFO 5
5 Span: W'-Z SW 2
4 6
N/S Wall near X' 16" SW l
2 3
near 52 E/W Wall on 52 16" SW l
1 2
Span: W'-Z 90002092
Page 4 of 4 Corrective Action Wall Thru-Wall Locat.on Thickness System OK Bolt Modify Total Turbino Building Diesel Generator B E/W Wall on 45 16" DFO 2
2 1
5 Span: S'-W' SW 1
3 4
E/W Wall on 52 16" SW l
1 3
5 Span: S'-W' l
Definitions:
Safety Injection (System)
=
Residual Heat Removal (System)
=
CVCS =
Chemical Volume and Control System SFPC =
Spent Fuel Pool Cooling (System)
Containment Spray (System)
=
Service Water (System)
=
SGBD =
Steam Generator Blowdown CSystem)
HVAC =
Heating, Ventiliating and Air Conditioning Diesel Fuel Oil System DFO
=
90002393
e ATTACHMENT 2 EVALUATION OF COMPOSITE WALLS METHODS OF EVALUATION The composite walla supporting safety-related piping are being evaluated to verify that these walls have adequate capacity to sustain piping loads.
The minimum thickness of composite walls ir 20 inches, with most of these walls boing 24 inches or larger.
S.ince these walls generally have a large capacity relative' to their supported loads, it is not expected that overstressed conditions (b33$ be found.
By review of walkdown data or architectural and piping draw-ings it was determined that approximately 64% of the composite walls in the Plant meet the acceptance criteria specified on page three of this attachment.
In order to expedite the evaluation of the remaining composite walls, init.a1 calcu-lations were made using the following simplified cons'ervative assumptions:
~
1.
Co ns id e r the wall to be a one-way alab myanning fsum floor to ceiling or between cross walls, whichever is the shorter span.
Ignore two-way pla te ac tion.
Hinged conditions are used for vertical spans.
2.
Assume that maximum tension and maximum VQ/It shear between masonry and concrete occur at the same location, 3.
Consider the ef fective width available to resist a con-centrated load t0 bc b
- 2t, where b is the width of the base plate and t is tht. thicknees of the wall.
This 90002094
a to supplement No. 2 Page 2 of 3 assumption of load distribution for the purpose of pre-liminary calculation is conservative with respect to the LER 79-15, supplement 1 criteria.
Acceptance criteria for the loads considered are given in Section 3 of Attachment 4 and Attachment 6 cf supplement 1.
Load combinations are in accordance with Attachment 4 of supplement 1.
If a wall satir.fies the acceptance criteria using the above assumptions, no further evaluation is necessary.
Further, if upon review of walkdown data or architectural drawings and previous analyses, it is determined that a wall clearly has smaller applied loads than a wall of substantially similar thickness and span which had been found acceptable, a detailed analysis is not necessary.
(The offect of openings, location of loads, and multiple loads are considered in this review.)
If the a~cceptance criteria have not been. satisfied by either of these methods, more detailed analyses will be performed.
In the first step of such detailed analyses, global bending moments resulting from out-of-plane seismic inerrial forces are calculated for the various levels of the buildings for each wall thickness.
Since the moments from the out-of-plane inertial forces are generally the same for each wall thickness between two floors in a building, generic calculations were performed to determine the difference between the moment capa-city of the wall and the applied moment from the out-of-plane inertial forces.
This difference was compared with the 90002095 m
. a me m eeem s' em
- m
. Attachment 2 to Supplement No. 2 Page 3 of 3 imposed coments from out-of-plane piping loads.
For combina-tion of in-plane and out-of-plane loads corresponding to a i
j horizontal component of motion, the resultant maximum rebar I
stress from out-of-plane bending was added to the reinforcing steel stress determined for in-plane bending at the appropriate wall location.
Acceptance Criteria l
Acceptance criteria shall be in accordance with Supplement 1,, Section 5.3, except that the maximum allowable principal tensile stress (as obtained using the method des-cribed in Attachment 7 to this supplement) between masonry and cor. crete core has been reduced to 40 psi.
70002096 m
W
&.S g e u pe u e m eW *
- A 1 & nt A 3 TROJAN NUCLEAR PLANT REPORT ON TESTING OF C0!e051TE MASONRY WALLS Nove=ber 1979 90002097 Portland General Electric Co.
Northwest Testing uberatories Wiss, Jar.ney, Elstser & Assoc., fr.:.
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Section 1 Test sujectives 1.1 The testing was performed in order to confirm the accuracy of our judg=ent with respect to the tension capacity at the interface between u.asonry block and concrete core of composite valls located in the Trojan Nuclear Plant.
The testing was performed "in-situ" on valls representative of the various types of cesposite walls at the plant.
J Figure 1.1 shows a cross section of the type of composite wall utilized An the facility, l
90002098 5
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Section 2 Nechodology 2.1 Location of test sites.
By inspection of Plant dravings, test sites which are representative of the ce=posite valls at the Plant and which are readily accessible in the present plant operating mode were chosen.
These chosen vere located at the 25' and 5' elevations in the Auxiliary Building and are shown in Figure 2.1.
Preli=inary exa=ination was conducted to assure that no wall attachments were present on either side of tne test region and to atta=pt to identify rebar that i
might interfere with the test.
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.i 2.2 Test preparation.
The testing pro 5 ram was conducted in two stages.
In the !1rst stage the bood strength between the f ront f acing block and the central cera concrete was tested and the second stage the bond strenSth be, tween the central core concrete and the rensining block at the sa=e sites tested in the first stage.
This procedure was followed with the exception of test No.1A where the second stage test could not be perfor=ed validly due to vall geo=etry.
2.2.1 First stage preparation.
A 12" dia. dianond drill type core borer was utilized to core through the f ront f acing block and into the concrete core, previding an "in-situ" sample 90002100
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of 11-!/2" dia. with a 1/4" annulus between it and the surrounding material.
i Block dimensions are 7-5/8" thick. To assure adequate penetration of the block the core bore was extended beyond that depth by ab:ut 1".
Initial placing of wedge anchors utilized one ef two recommended patterns as depicted in Figure 2.2.
Anchor bolts utilized vare 3/4" phillips vedge anchers sat to the manuf acturers recommandations a:d torquad prior to the coring operation.
The 11-1/2" dia. ecre was drilled cencentric around the 6" dia anchor bole pitch circle.
This method (utilizing three wedge anchors) was discontinued fellowing the first three tests due to the concern of possible bolt interaction and was replaced by a method utilizing ene central 1" phillips sedge anchor.
2.2.2 First stage testing.
The testing equipment utilized consisted of the following:
1.
Fabricated compression beam and bearing plate, hydraulic jack support bracket with 4 "C" clamps.
Figure 2.3 2.
Threaded 1" dia, red with nuts and coupling.
3.
Calibrated hydraulic jacking systen* censis:ing of:
a.
Enerpac Band Pu=p (SN 11754) b.
Enerpac 30 Ten Ram (SN 11752) c.
Ashcroft 3000 PSIG Hydraulic Cauge (5511755)
- This equipnent provided and operated by Northwest Testi.; Laboratories. See Appendix 1.
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CENTIR OF BLOCK l-ll i _g_ 4= 3/4" HOLE (TYP.) ,_i__ I ~ CCNTRAL ANCHOR 1" HOLE (TYP.) I f I != BLOCK JOINT (TYP.) 1 I d I CENTER OF BLOCK J = g l i i N l { ~ __L. \\_. --- a-- 90002103 / u FIG. 2.2 _ _
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Q d. Ashcroft 6000 PSIG Hydraulic Cauge (SN 11757) e. Multi-port Hydraulic Coup 11ngu and Hydraulic Hose. 4. Two dial micrometers The assembled test rig is shown in Tigure 2.4 The testing was performed in accordance with SPT-51 (Special Plant Test - 51) Rev. 0 included here as Appendix 2. Results were recorded in accordance with SPT-51 and siso independently by the Northwest Testing Laboratory Representative. These results are reproduced in Section 3 o~ ahis report. 2.2.3 Second stage preparation Following completion of the first stage test for each test site and subsequent napping and photography of the broken section a 1" dia. phillips wedge anchor was set into the central core concrete,' concentric with the exLat-ing geometry, and further coring utilizing the 11-1/2" dia. core borer pror,eeded. The depth of the coring was deter =ined such that the inside surface of the re-r.aining block was just penetrated (no more than 1/8"). 2.2.4 Second stage testing The testing was perforted ac described in Section 2.2.2. Subsequent to the testing the broken sections were mapped and photographed. 90002105 O e M' e
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i qjr } [ lll C l PLAN VIEW i "C" CLAMP LO"tTICN TYP. ALL CORNERS I I I __ l [_._ _ _ ' __ l 3 R -. r j j q i EL EVATION 90002106 p 3 ogy L M e M.L\\ = F G. 2.4
[w Section 3 Results The test results were recorded by PCE personnel utilizing the dats sheet from SPT-51, Rev. O and were also recorded by Northwest Testing Laboratory Representative using standard laboratory worksheets. Appendix 1 provides a stus=ary from Northwest Testing Laboratories of the failure loads and cali-bration data for the test equipment. Appendix 2 provides a copy cf SPT-$1 (Special Plant Test Procedure). (The deflection data fro = the micrometers was disregarded due to the dif ficulty of obtaining representative readings). In addition, all test sites were mapped and the broken speciments photographed. SA The results are presented in cabulse for= Table 3.1. 1 90002107 ~ ee /F O e
l l TABLE 3.1 TABULATION OF TEST RP. SUI.TS NO. OF CYCLES 4 TEST ^ ^ ED IJ) CATION SITE PATIERN OF CORE AT Fall _URE 5,003# 7,500# 10,0008 15,000f 20,000f 2 Elev. 25' 5.3 8 1/16" 5 0 1 0 0 9,820f i 2A Elev. 25' Certral Anchor 20 1/2" 5 3 3 0 0 17,670f 3 Elev. 25' 5.2 9 1/4" 1 0 0 0 0 4,500f i 4 Elev. 25' 5.3 9" 5 2 0 0 0 7,120# 4a Elev. 25' Central Anchor 19 1/2" 5 3 3 0 0 24,500# 4 5 Elev. 25' 5.3 9" 5 0 0 0 0 4,730f 5A Elev. 25' central Anchor 19 7/16" 5 3 3 0 0 14,4608 q 7 Elev. 25' Central Anchor 9 1/8" 5 3 3 3 0 15,890f 7A Elev. 25' Central Anchor 19 3/4" 5 5 5 5 3 21,7908 i oo R Elev. 25' Central Anchor 9" 1 0 0 0 0 3,790f O IM BA Elev. 25' Central Anchor 22" 5 5 5 5 0 14,850f C 9 Elev. 5' central Anchor F 5 5 5 3 0 15,000# CD 9A Elev. S' central Anchor 12 1/8" 5 5 1 5 5 1 21,790f i 2
Sectics 4 Evaluation of Tast Results The testing results were evaluated by a representative of Wiss, Janney, Elstner & Associates Incorporaccd of Chicago. The report is attached as Appendix 3. 90002109 0 W e 1 8 u ; g 6 e e g e ge .7s,
NORTHWEST TESTING LABORATORIES At15 N. MIS 5tsstPPi AVENUE P' C* E O X 17II8
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~,....n.,.. November 19, 1979 Portland General Electric Company 121 S.W. Salmon Portland, Oregon 97204 Re: Trojon Nuclear Power Plant Report Of: Composit Wa!! Masonry Block - Concrete Core Interface Bond Testing Lead Application Eculpment Test Loads were applied by a calibratec hydraulle Jacking system consisting of the following: Enerpac hand pump (SN11754), Enerpac 30 Ton Ram (SN11752), Ashcraft 3000 Psig hydraulle gage (SN 11755), Ashcraft 6000 psig hydraulle gage (SN11757), Multi-Port hydraulle coupling and 25 feet of hydraulle hose. Test Site No. Ullmate Failure Loads (Pounds)* Cace Used.(PS11 1 Not Applicable / Hit Rebar in Block ~ 2 9820 6000 2A .1670 6000 3 4500 6000 4 7120 6000 4A 24500 6000 5 4730 3000 SA 14460 6000 6 Not Applicable /Not Composit Wall 7 15890 6000 7A 21790 6000 8 3790 3000 BA 14850 3000 9 15000 3000 9A 21790 6000
- Note : Failure. Loads determined by Mathmatical interpolation between adjacent calibration points.
90002110
Partland Genarol E12ctric Company Page ' Re: Trojan Nucelar Power Plant The test loading system, including hydraulic ram, couplings and pressure gages were calibrated on a Tinius Olson Testing Machine. Cartified accuracy of this machine was established December 7,197f b Cal-Cert Co. 8 L n l silts By hand pumping, a wic'e range of loads were applied to the est machine. These loads along with the associated gage pressures were recorded. This i was done for both the 3000 Psig PCE gage and the 6000 Psig Northwest Testing laboratory gage. Results of this callbaration follows: 2 Actual Lead (pounds) from Tinius Olson 3000 PSIC Gage 6000 PSIC Cage 320 100 200 950 200 30 0 1,690 300 375 2,390 400 475 2,500 430 500 5,000 800 875 7,500 1150 1225 10,000 1500 1575 12,500 1860 1925 15,000 2200 2275 17,500 2540 2625 22,000 2900 3000 22,500 beyond range 3350 25,000 beyond range 3725 27,500 beyond range - 4075 30,000 beyond range 4425 Respectfully, NORTHWEST TESTING LABORATORIES, INC. L Charles R. Lane, P.E. CRv12 90002111 Report No. 211094 ,.w.e...e.
Appax::>x 7 TROJAN NUCLEAR PLANT PORTLAND CINERAL ELECTRIC CORPAhi SPECIAL FLAAT TEST PROCIDtTRE - SPT-51 UST OF MASON?.! BOND TENSION TO CONORETI CORE IN XASONRY ELOCK WALLS Nove:nbar 15, 1979 Revi st or: 0 Approved by Original signed by C. P. Yundt Date U 79 90002112 !6 j
SFT-51 Ravicien 0 \\ TAB:,,E OF CONTENTS l l Section Page l 1 Objective 1-1 b 2 Acceptance Criteria 2-1 3 Prerequisites 3-1 4 Precautions 4-1 5 Instsuctions 5-1, 5-2 6 Data Sheet 6-1 7 Excepcions and Notes 7-1 9 r e '90002113 1 see f
SP*-51 2 Reviolan 0 ? 1.0 OMICTIVES 1.1 To determine tensile bond strength of masonry bleek walls (both composite and 16-inch or less block walls). Q e-9 9 E 90002114 t 9 O e T Page 1-1 201 = - ~ ~
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s SFT-51 Ravision 0 2.0 ACCEPTANCE CRITERIA 2.1 Apply load at required test points until core fails or load reaches 30,000 pounds. f 90002115 e l e e e 4 Page 2-1 2\\
SPT-51 Pa isien 0 1, ,i 3.0 FF2 REQUISITES 3.1 Hydraulic jack test stand fabricated. 3.2 Hydraulic jack test calibrated (2 gauges). 3.3 Calibrated dial gauges available for use (optional). 90002116 l Page 3-1 3b
SPE-51 Revision 0 4.0 PP2 CAUTIONS t 4.1 Ensure core drill is marked so that core depths does not exceed width of block plus 1 to 1 5 inches. 4.2 Area radiation monitors in vicinity may be affe:ted by core drilling. Notify Shif t Supervisor before commencement of core drilling. 4.3 Monitor shield walls after plug has been removed for possible changes in radiation levels. 90002117 l \\ Page 4-1 1 Z3
4 g $PT-51 R:visien 0 p-5.0 JKS RUCTIONS TESTING FROGRAM MASONRY BOND TENSION TD CONCRF.TE COPE 5.1 Tour tests shall be run. 5.2 Two tests shall be run with holes loested a follows: l - Center of 6" Belt Circle \\ [ ._ W. Block Joint (Typ) 3 3/4 Hole (Typ) j, 5.3 Two tests shall be run with holes located as follows: I I--Block Joint (Typ) t
- enter of Block I
3/4"."11 ole (Typ) I o 8 i i L._ 5.4 A 12*-diameter core shall be drilled concentric around bolt circle center line. The core shall be cut into the concrete fill between 1" and 1-1/2". 5.5 The hole shall be located to miss block reinforcing. The center of core shall be concentric with above bolt circle. 5.6 The masonry block bearing plate shall be set with 3-3/4" phillips vedge anchors. The wedge anchors shall be set using manufacturer's reco:: ended torque valves. One test shall be conducted using Phillips Self-Drilling Bolts and equal to those used durinB original plant construction. 90002118 Page 5-1 b
f.* SPT-51 z Ravision 0 5.7 The jack assembly shall be set such that the 1" threaded tod shall be centered on the block bearing plate. 5.8 The jack assembly shall be torqued snug before the jack assembly plate bolts are drilled and installed. t 5.9 Af ter the jack assembly is installed the jack assembly threaded rod shall be backed off to the zero reading rod tension. e 5.10 The testing shall be performed in four steps. Step la Apply 5,000 pounds load. Relieve loed. Repeat load cycle four additional times. Step 2: Apply 10,000 pounds load. Relieve load. Repeat load eyele four additional times. Step 3: Apply 15,000 pounds load. Relieve load. Repeat load cycle four additional times. r Step 4: Apply lead to failure or 30,000 pounds, whichever comes first. 5.11 Af ter failure the amount of load shall be recorded. Pictures of the failed core shall be taken and the failed core described. 5.12 Repair wall using non-shrink grout. 90002119 i tage 5-2 2E5
SPT-51 B-Revisisc 0 Date DATA SHEET Time Start A separate data sheet will be co:pleted for each core drill specimen. 6.1 Location of core drill specimen:_ 6.2 Type of bolt pattern! 6.3 Serial No. hydraulic jack: Date gauge (s) calibrated: inches. 6.4 Depth of core drilled: inches. Diameter of core: Calculated area of cores square inches. 6.5 5,000 lbs. 10,000 lbs. 15.000 lbs. TEST STEPS Measured Measured Measured Measured' Deflec-Deflee-Deflec-Deflee-Initial tion Initial tion Initial tien Initial tion Apply (1) Lead l Relieve Apply (2) Load Relieve Tp~ ply (3) _ Load Relieve Apply (4) Lead Relieve Apply (5) Lead i I Relieve 6.6 Lead applied at failure: or maximum load reached 'ithout failure: Page 6-1 i I 90002120 ze 4.' S
t;rs ~a s R;visica O t?' t 7.0 IICIPTICNS AND NOTES 90002121 1 1 .i e I Page 7-1 U
t APPENC>l K b + EVALUATI,0N OF TESTS OF TENSII.E BOND STRENGT!! W 0F s. CC'iCRETE BLOCK TO FIR J IN THE a D TROJAN NUCLEAR POWERl LANT E NEAR PORTLAND, OREGON Y* Ej k'JE No. 79731 3 1 D e i a n d A 5 0 C i I 90002122 e 3. l n C.
- 'ISS, JASNO, EL?tNER AND ASSO::IATES INC.
= 330 ?:ingsten Road I; ::hbreci, 1131nois 60052 212/272-7400 Novc=her 24, 1979 ze twe@ s w
?; EVALUAT10N OF TESTS OF TENSILE BOND STRENC"H OF k CONCRITE BLOCK TO FIT.L W IN THE I s , TROJAN NUCLEAR POWER PLG'T S' T NEAR PORTLAND, OREGON J n U WJE NO. 79731 e J. Y. ~ E November 24, 1979 1 s t INTRODUCTION _ n c T At the request of Mr. Don Broehl of the Portland General Electrie n d company, an evaluation was made of the results of 15 tests on the com-A posite block a'nd concrete fill walls in the Trojan Nuclear Power Plant. s 5 s D - These tests, conducted by Norchvest Testing Laboratories, were intended t 1 l to provide a measure of the tensile bond strength be* veen the block and e A 1' fill. i 1 1[ Following the notice en November 19, 1979 to proceed, an inspection of the locations where the tests were perf or=ed was made en November 20, 1979 by Dr. John M. Hanson of Wiss, Janney, Elstner and Associates Inc. in the company of Mr. Frank Regan of PGE. A copy of a letter from t Northwest Testing Laboratveics, dated Novenber 19, 1979, sumr.arizing the test results was received at this time, along with a copy of the test data and a set of photographs showing the locations of the tests and the pieces removed from the valls. 90002123 @
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s, E Tests were conducted at ninc selected locations en Levels 5 and 25 in the Auxiliary Building. The testing was carried out, as, illustrated in Tig. 2(a), by using a hollow-core drill with a dia:eter ^ of approxinstely 12 in. to make a cylindrieni eut en a bori: ental W { axis into the walle. This cut was made up to 1 12. deeper than the L ( junction between the block and the concrete fill. A horizontal pull-y a U out force, P, was subsequently applied using an hyderulic jack to the D E y, exposed surface of the core. In most of the teses, this forca was E j spplied by means of a 1-in. dia. expansion anchor se'. along the exis 5 [ of the core. Flowever, in three tests, che f orce was applied threngh I three.3/4-in. dia, expansion anchors and a plate ceupled to a 1-1:. red. .J a n At six of the nine locations, a second test was conducted, as d g illustrated in Fig. 2(b), by extending the cori.; thr: ugh t.he con: rete sj fill and about 1 in. into the f ar block wythe. The procedure described g i in the preceding paragraph, using a centrally located 1-in, dia. expan-a t e sion anchor embedde:.1 in the concrete fill, was then repeated to obtain I a test at the junttien of the fill and fan wythe of blo:k. n '~ c. PIVIt'J OF T}lE TEST DA"A The letter from Northwest Testing Laboratcrries reporting the 15 test results is reproduced in the Appendix. It is car understanding that documentation of the tests, including their location and a descrip-tion of the surfaces where the cores were broken under the applied pull-out leading, will be provided in a separate report. l 90002125 t l. t e >
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9 A 1 N ~ _ ~ ~ . 6 e,. p ? d _ L.:. e +.. e ~. P jll " 4 c o R E. 1 7 ..- 7,. ) m ( .1 g.:. :_ v 5 *** e 1" 4 E X P, ANCHOR c '*. 6 r es a) - FIRST TEST 'I NEAR BLOCK 3 FAR BLOCK i r /- _. _._ _.. i __ P 68 t 6. u ____ P L.* L. m -. __._.._ J t L ,e 2 e .' g. b) - SECOND T E ST "A" Fig. 2 - Pullout Tests o [B 0$k N}h 90002126 ,5 5
1 i The test data and photographs of the locations of the tests and the pieces removed from the walls were carefully reviewed and the r,esults of this review are sucmarized in Table 1. l In examining the test results, it should be neced that pullout W l j loads are not reported for two tests, Nos. I and 6, because they are not I applicabic to this evaluation. j j For the reasons given in Table 1, only three of the remaining O D l }, 13 tests were considered to provide a valid measure of the tensile bond E strength at the block / fill interf ace. The other lo tests are considered i 5 1 to provide a lowcr bound estimate of the tensile bond strength, and for n this reason thesc results arc enciesed in pare = theses. a h INTERPRETATION A A s The applica:Lon of the pulloue load to the near block did nog g f develop the tensile bond strength of the block / fill i..tcrface in any tgst a [ except No. 3. Rather, the strength was 11=ited by conditions iciating s* 7 7 to the anchurs and to stress distribution within the near block. r y n C
- n Toct No. 3, the strength was deveicped beenuse the interface vas only partially bonded, apparently as a result of lack of consolidation of the fill concrete.
Although only two of the tests intended to develop the tensile bond strength of the fill with the back bleek vere considered to be valid, all of the other tcsts, except No. 5A, provide a reasonable lover-b und estimate of the strength. Test 5A is excluded bcesusc the anchor split the core, and the re.saining portion cf the core was broken out I l vith a wedge and h:mmer. The results of thesc tests, excluding No. 5A, i ~'~ 90002i27. l 1 me +hgg.
U Table 1 - Review of Test Results .L 6. Pullout Nominal Tensile Test cad (2) Bond Strength (3) Remarks g,, (1) ,) (psi) Invalid test, because dore did not cut 1 reinf orcing bar in block. .c. 2 9,820 (94) Core sustained 5 cycles of applied noninal loading to 5000 lbs, be. fore failing during first cycle while holding peak load. Test considered to be invalid because the core broke in the block and not at the block / fill inter-face. 2A 17,670 (170) core sustained 11 cycles of nominal leading - 5 to 5000 lbs, 3 to 7500 lbs, and 3 to 10,000 lbs - bef ore splitting and breaking under increased loading. Test considered to be invalid bceause break occurred in fill concrete about 2 in, from block. Splitting of core apparently caused by ancher bolt. 3 4,500 43 Failed before reaching intended peak load on first cycle. Valid because separation occurred at block / fill interface. Apparently fill con-crete did not bond to bic.k on about one-half of interfacc. L, 4 7,120 (68) Core sustained 5 cycles to 5000 lbs nominal leading and failed as peak load was reached during second cycle to 7500 lbs nominal loading. Test not valid because break occurred in block. 4A 24,500 236 Core sustained 11 eycles of oneinal leading, as described for Test No. 2A, before failure occurred under increased loading primarily at block / fill interface. Valid test, although the observation that the break surface departed from the block / fill interf ace around the peri-phery of the cere is considered to show that the applied tensile stress at the interface was higher at the center of the core than naar the periphery. 5 4,730 (45) Fa11cd during fif th cycle after reaching peak nominal load of 5000 lbs. Test invalid, because break occurred in the bicck. 90002128 _2 b i
c. Table 1 - Review of Test Result? (Continued) j Pullout Hocinal s Test (2) Tensile g,.,(1) ((bs) E#""E* (psi) SA 14,460 (139) core sustained 11 cycles of nominal loading, as described for Test No. 2A, before splitting under increased loading. Subsequently, a i vedge was hammered between core and vall, ~ causing separation at the block / fill interface. Test not valid as stress causing separation.is not known. 6 Not applicable, because vall was not corposite, at this location. 7 15,890 (153) Core sustained 16 cycles of nominal leading, including Il cycles as described for Test No. 2A plue 3 eyeles to 12,500 lbs and 3 cycles to 15,000 lbs, before failura under the first 1 cycle of an increased no=inal loading to 1 20,000 lbs. Test invalid, because break occurred main 2y within block, although a small portion of the piece that pulled out crossed the interf ace and extendec into the fill con-crete. l 7A 21,790 (210) Core sustained 23 cycles of nominal leading - 5 Lu 5000 lbs, 3 to 7500 lbs, 5 to 10,000 lbs, 5 to 15,000 lbs, and 3 to 20,000 lbs - before f ailure under increased loading. Test invalid, because break appears to have begun at the junction of the inside face of the block and the cell concrete, near the center of the core, and progrensed outvard through the block. 8 3,790 (36) Failed before reaching intended peak Icad on first cycic. Test invalid because core broke in block. Result van Ice because of void in a block cell concrete. 8A 14,850 143 Core mustained 29 cycles of nominal loading f ollowing the same pattern as in Test No. 7A, before f ailinc just prior to reaching the intended peak load of 15,000 lbs in the 20th cycle. Valid test, because break occurred sinly along bloch/ fill incerf ace, although it did extend into the fill concrete on a s all portion of the area. 90002129 _s-
s. G: Table 1 - Review of Test Results 3 (Continued) g' Pullout Nominal Tensile TeJ: L a (2) Bond Strength ( Eccseks g,,,,(1) (psi) o f 9 15,000 (144) Core sustained 17 cytics of neminal leading, following the name pattern as in Test No. 7A, 9 before f ailing as peak loading was reached in l' the 18th cycle. Test invalid because core broke in block. s SA 21,790 (210) Core sustained 21 cy:les of naminal loading, follouing the same patters as in Test No. 7A, before failing under increased loading. Test invalid because core broke mainly in block. although a small por: ion of the break surface J. occurred at block / fi'l interface. Core was [- apparently split by sucher bolt. (Fill is not as thick an other locations.) J' r 'I N:te s : 1 (1) Icsts vero conducted at ninc locations, as indicated by the first number of the = ark. At each location, designated by a number, the test was intended to apply a tensile strens to the interf ace between the ba:k face of the near j block snd the concrete fill. Where another test is ir.dicated by the letter A, a sc:ond test was condu:ted at the same location. This test was intended to apply a tensile stress to the interf ace hetween the near f ace of the back block ) and the concreLe fill. (1) As reported in letter to PCE from Northwest Testing Laboratories dated Nove:bar 19, 1979. (3) Determined assuming pullout load was uniformly distributed over 11.5 in. dia. Values ir parentheses arc considered to be results of invalid tests, core. although in every case they represent a lower bound esti=are of the tensile bond strength at the bisek/ftil interface. 2 90002130
are plotted in Fig. 3. The average bond strength developed in these .i g' 5 tests was 194 psi. [. In assessing the 5 test results shavn in Tig. 3. it may be noted that they have a characteristic variation that is expected in tests g. i dependent en the tensile strength of concrete. Furthermore, the s L everage bond strength of 194 psi is approximately one-tenth of the a a specified compressive strength of the block, which is a reasonable value n e y. for tensile strength. This result is also consistent with the observa-f tion that the break surface in the valid tests, Sos. 4A and BA, appeared s 1 to depend on the strength of the block concrete rather than the fill a e r concrete. It is considered desirable to establish a basis for using these d test results within the framework of the provisions of the ACI Building 4 .n sj Code Requirements for Reinforced Concretc (ACI 318-77) and the ACI c i Building Code Requirements for Concrete Masonry Structures (AC1531-79). a i The conditions at the interf ace of the block and fill concrete e 5. I are further considered to be similar to the conditions at a vertical n construction joint in monolithic concrete construction. With sufficient reinforcement across the joint to accommodate the internal force systes, m there is usually no need to provide any special treatment other than that tbc joint be clean and have some roughness. \\p the Trojan valls. structural intecritv n' -ke '-earfmee is recuired. and the amount of f a 4oint is neariv ncelitibic. j reinforce =ure In resisting shcar, the provisions of AOI 315-77 allow the use of flexural members without shear reinforcement if the factored shear force, V.,, does not exceed one-half the shear strength provided by the 90002131 =+=m-4e>-- eoes,+ me t
'G ' (' e Ave. Bond = 19 4 psi 236 / j' / (210) (210) ~~{ / 'l '/ i 200 (*. / / ~/ ~ / / ,/ j Nominal - (170 ) j/ / / I, Tensile / / / / / / -"143 / Bond ,/ / / 7 Strength / / / /j / i / / / / / (Ps ) / / / / / 10 0 ,/ / / / / / / / / '/ / / / / 's / / / / / / / h /(/ i-L. /, '/ '/ / / /, lf / / / / / // / / / / .i 2A 4A 7A SA 9A Test Mark Fig. 3 - Results of Lests on f ar b3ock interf ace ~2 - 90002l32
concreto, $ V,, where 4 is the strength reduction factor. This may be considered comparable to requiring a strength reduction factor of 1/2 9 where strength without refnforce=ent is re;nited. Since e for shear is specified to be 0.85 in the Code, the equivalent strength y i reduction factor is 0.425 for a flexural member withcut shear reinforce-s s. j ment. When shear is being resisted without reinforce =ent, the strength a is dependent on internal tensile stress in the cencrete. tI' T In our opinion, the conditions at the block / fill interface are f more critical than for shear as considered in the previous paragraph. ,hTb Based on the limited test data and our knowledge cf the conditions in it 1 e y the composite valls at the Trojan Finnt, a strength reduction factor of a } 0.2 is judged to be appropriate. On this basis, the =aximum tension p permitted across the block / fill Interface under factored loads should 5 be 0.2 x 194 = 39 psi, or say 40 psi. I By using a strength reduction factor of 0.2, it =ay be noted that a 1 the bond strength is taken to be slightly less than the bond strength of ik 43 psi obtained in Test No. 3. If there are other areas where there is t. littic or no bond between the block and fill, they are believed to be small and scattered, since the valls at the Trojan Plant were constructed under a quality control program that is understood to have required thorough consolidation of the fill concrete. 9 In addition, assuming that the ratio of factored to service leads 1s 1.5, the stress at -l the block / fill Interface sheald not exceed about 25 psi. It may be noted that this icvol of tensile stress is allowed O normal to bed joints in hasonry construction containing hollow units in ACI 531-79. ii ~ 90002133 < 7()- 7'
.:.e V Considering a cubical element at the bioch!ff.11 interface, with one f ace parallel to the interf ace, states of stress varying f rom pure normal stress to pure shcar stress are :heoretically possible. W The resistance of a monolithic mass of concrete to sheJLr is greater j 5 8-than its resistance to tension. Since the tests de nonstrated that J the bond at the block / fill interface was comparable te the tensile n a D a e strength of the block concrete, it follows that tensten' at the inter-r ),. E face will be core critical than shear. However, states of stress that I 3 include shear at the interface may have a principi tensile stress o acting at an angle to the interfacc. By limiting the max 1=u= principal E } tension at the interf ace to 40 psi, the potentia'. for initiation of a .:r, n d a crack that might change its direction and proptgate along the inter-A 3 face is mitigated. 0 C In this regard, it should be recognized tha: a; plication of a t forces that cause stresnes exceeding the tensile strc.gth of the e 5. valls at their boundaries will cause cracking that =47 pene: rate the i S block / fill interface. In this state, the ' stress at the interface will be more dependent on local conditions; i.e.. reinf or:s ent in the vn11 or location of supports on the vall. E:vever, limitation y. of the tensile stress under factored loads at the bic:k/ fill interf ace 5 to 40 psi, aleng with consideration of the local ef fect of the crack-ing, is believed to be suf ficient to assure integrity. e 90002134 . 45 = es ..y
? ?< 9 & CONCLUSIONS i i. Review of test data obtained fro core pullout tests on the composite block and fill concrcte valls in the Trojan Nuclear Power 1 Y Plant has shown that a high Irvel of bond exists at the block / fill 3 5 A interface when the construction is as intended by the project specifi-cations. This bond strength is believed to be closely related to the n n tensile ' strength of the concretc in the block. The average bond in e y, g 5 teste selected as pro'viding a reasonable measure of the bond strength 1 s was 194 psi. t n e In view of the lack of bond encountered at one of the 13 locations I a where tests of the interface were performed, as vell as the recognition n d that structural integrity is required in the absen:e f reinforcer.ent, A s it $s our opinion that a conservative strength reduction factor must be s o C applied to the bond strength. A value of 0.2 is recemer.nded, which e-1 a t limits the tensile bond stress to 40 psi under factored loads. This e 8' limit is consistent with the icvel of tensile stress that is allowed in I { eencrete masonry construction. Respectfully sub=1tted, WISS, JANNEY, ELSTN:2 AND ASSOCIATES, INC. 4*A ', '.i ~)'d.,*g '<.g{p'. ', John M. Hanson Project Manager Registered Prof essienal Engtnear j,/,y' O g , g Ci i., ', O. j g/il; State of Oregon No. 10110
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a. e NORTHWEST TESTING LABORATORES 4115 N. M I S S I E S I P P I A V E N U C P. o. p o X 17125 .arnwem tenia.e P Q R T L A N D. O M E G O N 9 7 217
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m a rs eiaL. sa.**ct*** ~;,;e;; ... 6n.n. November 19, 1979 i .L Portland General Eicctric Company 121 S.W. Salmon C Portland, Oregon 972G4 Re: Trnjon Nuclear Power Plant 5,: Report Of: Composit Wall Masonry Block - Concrete Core Interface Bond Testing Load Application Equipment Test Loads were applied by a calibrated nyorauli: Jacking system consisting of the following Encrpac hand pump (SN11754), Enerpac 30 Ton Ram (SN11752), Ashcraft 3000 Psig hydraulic gage (SN 11755), Asheraft 6000 l psig hydraulic gage (SN11757), Multi-Port hydraulle coupling and 25 feet of hydraulic hose. .g Test Site No. Ullmate Failure Loads (Pounds)* _Cace LLsed (PS Not Applicable / Hit Rebar in 31ock 1 h' 2 .9820 6000 ) .y 2A 17670 6000 3 4500 6000 4 7120 6000' t 4A 24500 6000 5 4730 3000 ~ SA 14460 6000 6 Not Applicable /Not Composit Wall 7 15890 6000 7A 21790 6000 8 3790 3000 8A 14850 3000 9 15000 3000 9A 21790 6000
- Note:
Failure Loads determined by Mathmatical Interpolation between adjacent calibration points. 90002137 = r' s
- * * * * * =
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1 Portland Censrst Elsctric Ctmpany Page.. Re: Trojan Nucalar Pswer Plant The test loading system, including hydraulle ram, couplings and pressure i t: Certified gegos were calibrated on a Tinius Olson Testing Machine. accuracy of this machine was established December 7,1974 by Cal-Cert Co. 1, ! By hand pumping, a wide range of loads were applied to the test machine. These loads along with the associated gage pressures were recorded. This was done for both the 3000 Psig PCE gage and the 6000 Psig Northwest Results of this estibaration follows:
- f.
Testing laboratory gage. .c j Actual Load (pounds) j. from Tinius Olson 3000 PSIC Coge 6000 PSIG Gage lC 320 100 200 950 200 30 0 300 375 '.M 1,690 475 400 2,390 500 L'i 1830 I' 2,500 875 5,000 800 1150 1225 7,500 s:' 10,000 1500 1575 1860 1925 in 12,500 2275 2200 id.: 15,000 2625 2540 17,500 3000 2900 22,000 g:' ~ 22,500 beyond range 3350 25,000 beyond range 3725 7-4075 f 27,500 beyond range e 4425 30,000 beyond range k' Respectfully, NORTHWEST TESTING LABORATORIES, INC. e V.L ~ CA A ~ Charles R. Lane, P.E. 90002138 Report No. 211094 1 .4..
O ATTACHitENT 4 FIELD SURVEY OF CONCRETE WALLS, FLOOR SLABS AND STRUCTURAL STEEL A field survey of concrete walls, floor slabs, and structural steel at Trojan was conducted by two licensed civil engineers, one from Bechtel and one from PGE, and one PGE mechanical engineer who had detailed knowledge of the Trojan Plant piping systems. The purpose of the field survey was to identify, for further detailed evaluation, specific installations where the loads from a safety-related pipe support were judged to be high relative to the capacity of the supporting structure. In preparation for the field survey, preliminary calculations were made fer typical structural configurations. In addition, pipe supper: details for large pipelines were studied to deter-mine the range of possible loads. The original floor system design criteria had an allowance of 50 pounds per square foot to account for pipe loads and a 5000 pound load applied anywhere to beams to provide for lif ting and pipe supports. After studying this information, it was apparent that only certain adverse loading conditions could overs' tress the various structural members. For example, weak axis bending, torsion or local distortion are the most likely adverse loading conditions for steel members. For concrete walls and floor slabs, the most adverse loading condition is the normal load and banding moment at the base of a pipe support. During f the field survey, particular emphasis was placed on any area where such conditions could exist. Multiple supports on a structural member was also of special interest. The supports for the saf ety-related piping in the Containment, Auxiliary & Fuel Buildings, Main Steam Support S truc tur e, 90002139
), . Attachment 4 to Suoplement No. 2 Page 2 of 3 Emergency Diesel Generator Enclosure, Auxiliary Feedwater Puhip Enclosure, and Intake Structure were inspected. The Control Building and ESF Switchgear Enclosure wpre not inspected since drawings indicated the piping in these areas is small and incapable of overloading the structural elements to which the pipe supports are attached. The following items were considered in identifying strictures more heavily loaded relative to their capacity: 5. Number of piping restraints on the structural element. 2. Size of piping and piping restraints. 3. Location and type of restraint reaction, i.e.
- tension, compression, bending or shear, and relationship to principal axes of the structural element.
4. Dead load on the structural element. 5. Live load, other than pipe restraint reaction, on the structural element. ~ 6. Seismic response of the structural element. 7. Ploor slab thickness, span to thickness ratio, and reinforcing for concrete slabs. 8. Size of framing for braced systems, and span to depth ratio for beam-girder systems. Based on the allowances in the original design criteria de-scribed above, it was obvious that the majority of the supports could not contribute significantly to the overall loading of the supporting structural elements and that resultant loads fell well within these design allowances. 90002140
- b
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' to Supplement No. 2 Fage 3 of 3 Such supporting structures were determined to be adequate by inspection. The survey identified fourteen supports for further evaluation. Of these 14 supports, 5 involved structural steel members and 9 involved concrete floor slabs. No sopports on concrete walls were identified for fu.rther evaluation. 90002141
l s 1 ATTACHMENT 5 MORTAR BETWEEN WYTHES OF DOUBLE-BLOCK WALLS Recent inspections in the field have found that some 14-in. and 16-in. thick double block walls are not f ully mortared between wythes. This information contradicted information de-veloped from drilling for thru-bolting masonry walls which in-dicated approximately 90% mortar between wythes. A review of construction records indicates that the above walls were erected during a limited time period in 1972. As a result, walls constructed during that time period which rely upon mortar for interf ace shear transfer will be inspacted. Where mortar is incomplete the inter-wythe space will be filled with non-shrink grout. In performing a tensile-bond test of composite end mortared double-block wall interf aces in November 1979, PGE found one double-block shield wall at Elevation 5 f t in the Auxiliary Building where mortar was incomplete in the inter-wythe space along three courses of block. Inis discovery led PGE to investigate whether there were any significant void areas in the mortar of the three mortared double block masonry walls which are major shear walls in the Control-Auxiliary-Fuel Building Complex. Tests were done on these three walls (control Building R-Line wall between Elevation 65 ft and 77 ft, control Building N-Line wall between Elevation 65 ft and 77 ft and Auxiliary Building 46-Line wall between Elevation 61 f t and 77 f t). Drilling of 1.5 inch cores into tre inter-wythe space showed that 90002142 e R MM
At ta'chment 5 to Supple =ent No. 2 Page 2 of 3 only one of these walls (the R-Line wall) had void areas in the mortar space. The voids found in the R-Line wall and the test holes on all three walls were filled with non-shrink grout. A check of QA records indicated that the R-Line wall was the only one of the three which was erected during 1972. During similar tests on walls of the emergency diesel generator enclosures, the north wall (column line 45) was found to be . s \\\\ . to Supplement No. 2 Page 3 of 3 and was settled in Septe=ber 1972. Because of this dispute and the evidence we found, we have less confidence that the inter-vythe space is properly mortared in valls built between April and September 1972. Although mortar should have been placed between the wythes in compliance with the drawings through the entire period, we recognize that contractural disagreements between contractors and construction management are sometimes reflected in the quality of the work. Since testing of two of the walls constructed during the period between Apri' and September 1972 disclosed sece large voids in the inter-wythe mortar, we are proceeding to test all double-wythe walls built during 1 this period to verify the adequacy of m=r:ar in the inter-wythe space. Where voids are found, they will be filled with n0n-shrink grout, as have all voids found to date. 90002143 np4-O+d g',
- m
. to Supplement No. 2 Page 3 of 3 and was settled in September 1972. Because of t:is dispute and the evidence we found, we have less confiden:e tha t the inter-wythe space is properly mortared in walls built between April and September 1972. Although mortar should have been placed between the vythes in compliance with the drawinge through the entire period, we recognize that contractural disagreements betvoen contracters - and construction management are sometimes reflec ed in the quality of the work. Since testing of two of the walls constructed during the period between April and September j 1972 disclosed some large voids in the inter-wytte mcrt a r, we are proceeding to test all double-wythe walls suilt during this period 1 to verify the adequacy of mortar in the inter-wythe space. Where voids are found, they will be filled with non-shrink grout, as have all veids found to date. O D ? \\ b oo m . Ak e, o o 1 Mortared double wythe masonry walls built durin; the period from May through September 1972 are lis ted or. the attached table. 90002144
/ a to Supplement No. 2 TABLE 5-1 Mortared Double Wythe Walls Erected Mid-1972 t .. a Colura Between Masonry Building Elevation Line Lines Insoection Date Control 61/65 R 41-46 6/27/72 Auxiliary 5 46 D-E 6/23/72 Emergency 45 52 U-S' 6/29/72 Diesel 45 52 X'-Z 7/10/72 Generator 45 52-W' Room 6/29/72 ESF 69 46 U-Y' '6/9/72 Switchgear 69 51 X'-Y' 6/9/72 69 51 x'-y' 6/9/72 69 '51-W' 6/9/72 90002'45 1
6 ATTAC11 MENT 6 APPLICA31LITY OF THE 1.8E LOAD COMBINATION In response to a question from the NRC staff, this dis-cussion will explain why the equation found in Section 3.8.1.3.2.1 of the FSAR, which requires that " structural ele-ments carrying mainly earthquake forces, such as eculp ent supports" be designed for 1 8 times the OBE loading is not applicable to the design of walls in the Trojan Plant, but rather is applicable only to the design of concrete pedestals for equiptent. Section 3.8.1.3.2.1 contains a list of equations w ich are ap-plicable to all Category I concrete structures. I: is logi:a1 to assume that the additional equation cited above was not included within that list because it was intended to apply only to a limited subcategory of concrete structures, i.e., those " carrying mainly earthquake forces, such as equipment suppor ts. " It is appropriate to apply a higher load factor to equipment supports than to walls because the seismic capabi*ity of the equipment support could more directly affect the performance of an important piece of equipment. Eartnquake forces are one of the main forces normally considered in tne design of equipment pedestals. This is not the case for walls supporting piping where piping dead loads and thermal loads are generally much more significant than their seismic con tr ibu tion. Further, the piping supports, being spread along a run, are inherently more forgiving if one snould f ail. Hence, the safety factor need not be as conservative for piping as for equipmer.: supports which are directly dependent on pedestal integrity to maintain functional capability. We ma-2 .,y a w ja 90002146 x- ,,u -ermM wee .pg.,
t to Supplement No._2 Page 2 of 3 believe this is the basis for the additional conservatism for equipment supports. We have researched the origin of this equation a.7d its application in the design of supporting structures in other plants licensed in the, period during which Trojan was licensed. This research did not conclusively establish the origin of this equation for Trojan nor did it provide a precise definition of the specific structural elements to which it should be applied. However, the research did develop some usef ul infor-mation reflecting how the Atomic Energy Commission (" AEC") may have interpreted the equation at the time Trojan was being licensed. A paper, dated August 11, 1970, entitled, " Seismic Design Criteria for Nuclear Power Plants", written for the AEC contains a load combination which in luces the 1.8E f actor for the design of concrete equipment pedestals. This paper does not contain any other teference to the use of a 1.8 factor for OBE loads. Therefore, in the absence of further evidence, it would appear that when Trojan was being licensed, the AEC would have interpreted the equatien in Section 3.8.1.3.2.1 of the FSAR to only be applicable Lv cuncteLe equ196ent pedes Ld18. we have reviewed the design of concrete Category I equipment supports at Trojan and have found only six supperts where this load equation would be applicable, i.e., only six concrete pedestals. These are supports for the containment spr ay pumps, RER pumps, and RER heat exchangers. We have analyzed these supports using the equation containing the 90002147 e f['r
e a , to Supolement No. 2 Page 3 of 3 1.8 E Icading combination and have found that they satisfy the acceptance criteria. It should be notec that majer j equipment supports such as for the reactor vessel, steam generators, etc, are structural steel and, therefore, the l subject lead equation is not applicable. For the above reasons, we believe that the referenced equa-tion has been appropriately applied for Trojan. 90002148 h +
~~ s, 4. 4 ATTACHMENT 7 SHEAR-TENSION INTERACTION Where a composite wall is subjected to a ecmbination of out-of-plane loadings which include concentrated pipe restraint reactions and the wall's own inertial loading, it is theoret-ically possible to develop states of stress at the block-concrete interface which vary from pure normal stress to pure shear stress. Results of investigations carried out on con-crete have indicated that the resistance of a monolithic mass of concrete to shear is greater than its resistance to tension. However, the state of stress that includes both tension and shear may have a principal tensile stress acting at an angle to the interface. Thus the criterion that is used to evaluate the composite walls is based on conservatively limiting the principal tensile stress to 40 psi (See Attachment 3). The interaction equation that will be used for evaluation of shear and tension acting together will be as given in tae paper, " Behavior of Concretc Masonry Under Biaxial Stresses", by Hagemier, Nunn and Arya, which was presented in the North Anerican Masonry Conference (August 14 thru 16, 1978, Univer-sity of Colorado). The equations are as follows: tan 20 = - 2-
- X
- X e
= 2 Ces 20 s i sin 2e 1,2 2 2
- Where, 8
= tensile stress normal to block-cencrete interface x = shear stress 1,2 = principal stresses = angle of plane or. which the principal stress develops e 90002149 i I _...}}