ML19305B718
| ML19305B718 | |
| Person / Time | |
|---|---|
| Site: | 07000754 |
| Issue date: | 01/31/1980 |
| From: | Mcdonald J, Mehta K, Danni Smith TEXAS TECH UNIV., LUBBOCK, TX |
| To: | |
| Shared Package | |
| ML19305B699 | List: |
| References | |
| NUDOCS 8003200133 | |
| Download: ML19305B718 (63) | |
Text
O EFFECT OF NATURAL 3FE40ME4A ON EXISTING PLUTONIUM FABRICATIO4 FACILITIES Response of Structures to Wind Hozord at the General Electric Vollecitos Nuclear Center Vollecitos, California i
VclumeI ns:itute for Disaster TesearC1
~~EXAS ~EC-U N l'vE TS ~~Y
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,e THE EFFECT OF NATURAL PHENOMENA ON EXISTING PLUTONIUM FABRICATION FACILITIES RESPONSE OF STRUCTURES TO EXTREME WIND HAZARD at the GENERAL ELECTRIC VALLECITOS NUCLEAR CENTER Vallecitos, California VOLUME I by Kishor C. Mehta Douglas A. Smith James R. Mcdonald Institute for Disaster Research Texas Tech University Lubbock, Texas January 1980 Q
FOREWORO The U.S. Nuclear Regulatory Commission has undertaken a project to analyze the effects of natural phenomena upon exist-ing plutonium fabrication facilities.
The work is being accomplished by a task force of experts who are contributing to the various phases of the project.
This report is one of a series of reports, to be produced by Texas Tech University, w;11ch examine the response of structures and the damage consequences to a specific existing plutonium fabrication facility caused by severe wind.
The General Electric Company Vallecitos Nuclear Center (VNC) facility located at Vallecitos, California is the subject of this report.
Volume I of this report presents the methodology, the basic data, the results and the con-clusions of the study.
Volume II contains the structural calculations on which the results are based.
The project tasks are performed by Texas Tech University under subcontract from Argonne National Laboratory (Contract Number 31-109-38-3712).
Mr. James E. Carson, Division of Environmental Impact Studies, Argonne National Laboratory, is the project manager.
Dr.
James R. Mcdonald and Or dishor C. Mehta of Texas Tech University are the principal investigators for the project. Mr. Douglas A. Smith of Texas Tech University serves as research associate.
The project is coordinated through the Department of Civil Engineering and the Institute for Disaster Research, Texas Tech University.
e i
c TABLE OF CONTENTS Pace FOREWORD i
TABLE OF CONTENTS 11 LIST OF FIGURES iii LIST OF TABLES iv I.
INTRODUCTION 1
II.
STRUCTURAL SYSTEMS AND MATERIAL PROPERTIES 3
A.
General Layout of the VNC Facility 3
B.
Structural Systems 5
C.
Material Properties
- 1 III.
STRUCTURAL RESPONSE AND DAMAGE CONSEQUENCES 23 4
A.
Threshold Windspeeds to Produce Damage 24 B.
Atmospheric Pressure Change (APC) 28 C.
Combination of Wind and Atmospheric Pressure Change 30 D.
Numerical Example 31 E.
Windborne Debris 34 F.
Exhaust System 34 G.
Damage Consequences 36 IV.
THRESH 0LO WIN 0 SPEEDS AND FAILURE MODES 39 A.
Damage to Building 102 39 B.
Damage to Exhaust System of Building 102 43 C.
Damage to Building 102A 45 D.
Damage to Building 105 46 E.
Windborne Debris Damage 46 F.
Summary of Failure Modes 47 V.
DAMAGE SCENARIOS 50 A.
Damage Scenario for Nominal Windspeed of 95 mph 50 B.
Damage Scenario for Nominal Windspeed of 135 mph 51 C.
Damage Scenario for Nominal Windspeed of 180 mph 53 0.
Damage Scenario for Nominal Windspeed of 230 mph 54 VI. REFERENCES 56 11
LIST OF FIGURES Figure Page 1
Layout of the 100-Area of the VNC Facility 4
2 Basement Plan of Suilding 102 with Areas of Concern 6
3 Ground Floor of Suilding 102 with Areas of Concern 7
4 Vault and Surrounding Lab Area in Building 105 8
C 5
Typical Column Connections in Building 102 10 6
Layout of Structural Walls in Building 102 12 7
Precast Concrete Wall Panel Connections at Steel Columns in Building 102 13 8
Anchorage Detiils of Concrete Block Walls in Building 102 15 9
Typical Structural Features of RML Cells in Building 102 16 10 Ficor Slab Over Basement in Building 102 18 11 Wind Pressures on a Buildin9 25 12 Column Reinforcement Used in Numerical Example 32 111
LIST OF TABLES Table Page I
Material Properties 22 1
II Tornadic Windspeeds, Atmospheric Pressure Changes, and Ventin9 29 III Windstorm Generated Missile Velocities 35 IV Damage Consequences 38 V
Threshold Windspeeds for Damage to Building 102 49 4
iv
1 I.
INTRODUCTION This report is part of a study sponsored by the U.S. Nuclear Regulatory Comission to assess the potential radiological con-sequences of natural phenomena (flood, earthquakes, and severe winds) on existing plutonium fabrication facilities.
The study involves determination of hazard risk, structural response, source term, dispersion, demographic patterns and dose levels.
The paper by J.A. Ayer and W. Burkhardt, " Analyses of Effect of Abnormal Natural Phenomena on Existing Plutonium Fabrication Plants" [1]*,
provides background on the overall hazards evaluation.
The response of structural systems and components to wind hazard at the General Electric Company Vallecitos Nuclear Center (VNC) facility located at Vallecitos, California is the subject of this recort.
The windstorm risk assessment was made by Fujita [2] based on tornado and other severe wind records from the geographical region surrounding the plant site. The windstorm hazard at the site con-sists of straight line winds or tornadoes and is expressed in terms of expected value of windspeed for a given probability of occurrence.
Associated with tornadic windspeeds are implications of atmospheric pressure change and windborne debris.
Structural response of the building and potential of windborne debris are expressed in tenns of threshold values of windspeed to produce postulated damage to the building enclosure. The damage postulation is based on seven years of windstorm damage investigation experience involving more than thirty windstorm incidents by the senior authors.
The structural response and missile imoacts are
- Numbers in brackets pertain to References,Section VI
2 subsequently translated into consequences of damage to glove boxes and filters.
These consequences then provide information to the source term evaluators, who, in turn, determine the amount and form of plutonium that would be available for dispersion into the atmosphere.
The type of structural systems and construction material prop-erties at the General Electric VNC facility are discussed in Section II of this report.
The structural systems and the material properties are documented frcm the drawings and specifications made available, the EDAC Task I report [3] and the site visit.
A general discussion of structural response to the windstorm hazard, including the effects of wind, atmospheric pressure change and windborne debris, is con-tained in Section III.
In addition, the consequences of damage to glove boxes and filters are defined in Section III.
Section IV contains postulated failure modes, calculated threshold windspeed values, and damage summary for the General Electric facility. Actual calculations of the values presented in Section IV are contained in Volume II of thisreport[4].
Senarios of expected structural damage and the con-sequences of damage to plutonium containments for selected windspeeds are presented in Section V.
3 II. STRUCTURAL SYSTEMS AND MATERIAL PROPERTIES In this section the stractural systems employed in the build-ings of concern at the General Electric Vallecitos Nuclear Center (VNC) facility are described, and the material properties which are common to them are defined.
The areas of concern in each building are limited to a specific portion of the building.
These portions of the building and the features of their structural systems which are critical to wind hazard assessment are presented here.
The re-sponse of the structure to wind hazard and missile impact, as presented in this report, is restricted to the designated areas of cencern. The other areas of the building are considered in analysis of the wind hazard to the extent that their structural response may have an effect on the areas of concern.
A.
General Layout of the VNC Facility Layout of the 100-Area of the VNC facility is shown in Figure 1.
Plutonium material is handled in two buildings at the VNC facility; Building 102 and Building 105.
Building 102A is the mechanical equipment building, containing the fans and the final HEPA filters for the air ventilation exhaust system of Building 102. Mishima [5]
has identified specific areas.of concern in these three buildings.
Building 102 has two floors, a basement and a grcund floor.
The areas of concern in the building are the Plutonium Fuel Lab-oratory (PFL), the Radioactive Materials Laboratory (RML), and the P.A.L. Chemistry Laboratory (PALCL).
The PFL is located in the
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The PFL contains several glove boxes which are the items of major concern.
The RML cells and the PALCL area are located on the ground floor (see Figure 3).
The RML cell structure extends below the ground floor, but is independent of the building basement. The ground floor contains other non-critical laboratories, offices, and service areas.
The mechanical equipment Building 102A contains the fans and the final HEPA filters for the exhaust system of Suilding 102. A 60 inch diameter stainless steel duct transfers the exhaust air from the roof of Building 102 to the roof of Building 102A.
The duct is supported on a steel truss bridge.
The exhaust air from the glove boxes and critical areas pass through two sets of HEPA filters, in series inside Building 102, before it enters in the duct at the roof top of Building 102.
The vault and CEF cell are the areas of concern in Building 105 (see Figure 4).
Plutonium in the form of powders, liquids, and completed fuel rods are stored in this area. All the stored plutonium is contained in multiple barrier vessels inside the vault. A breach in the structural integrity of the Building 105 is not likely to expose plutonium to the atmosphere.
B.
Structural Systems The areas of concern at the General Electric VNC facility are the PFL, RML cells, and PALCL in Building 102, the air ventilation exhaust system of Building 102, the HEPA filters in Building 102A, and the vault and CEF cell in Building 105. The structural framing
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VAULT AND SURROUNDING LAB AREA IN BUILDING 105 i
9 and architectural systems which are pertinent to windstorm damage investigations of these areas of concern are described here.
1.
Buildina 102 This building is of one-story construction with a partial base-ment and with a high bay RML cell area.
The plan view of the ground floor with designated areas of concern is shown in Figure 3.
The ground floor is approximately 140 ft x 228 ft in plan.
The Annex (see Figure 1) is structurally separated from Building 102 and need not be considered in this study.
The ground floor exterior walls are 6 in precast concrete panels, metal siding, or glass panels. The interior walls are either rein-forced concrete block or 1/2 in. gypsum wa11 board on 2 x 4 wood studs.
The floor slab is a reinforced concrete flat slab over the basement and slab on grade elsewhere.
The structural system for the ground floor employed in this building consists of structural steel framing.
The roof is composed of built-up roofing on one inch of rigid insulation supported by Robertson flo. 3-16 gage metal roof decking.
The EDAC Task I report [3] assumes that the metal decking is welded to the steel beams.
The structural steel frame in Building 102 has typical column spacing of 20 ft. in both directions.
The roof beams are simply supported at the columns.
Columns are simply suoported at the bottom.
Figure 5 shows typical column-beam and column-base plate connections.
The column section is a hollow square section made by welding two 5 x 5 x 5/16 in. angles along their length.
The roof beams are wide flange sections.
Diagonal bracine 1: provided for the steel frame
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TYPICAL COLUMil CO?!?lECTI0tlS I!! BUILDING 102
11 in the high-bay area.
Shear walls provide lateral load resisting system for the remainder of the building.
The exterior walls of Building 102 are constructed of precast concrete panels, reinforced concrete masonry, or glass panels as shown in Figure 6.
Interior walls are either reinforced concrete masonry or gypsum wallboard on 2 x 4 in. studs.
The interior walls which act as shear walls are shown in Figure 6.
The precast concrete wall panels and the reinforced concrete block walls act as shear walls to resist lateral loads.
The precast concrete wall panels are anchored to the structural steel framing at the top edge of the panel. Welding inserts imbedded in the precast concrete panels are used to form the connections. A 2 in. by 5 in. recess is provided at the floor slab edge as a seat for the precast wall panels.
The bottom of the precast wall panels are connected to the supporting reinforced concrete slab by steel inserts in both the wall and the slab which were connected by field welding during erecticn. Along the sides, the precast concrete wall panels are connected to the steel columns by steel inserts grouted with poured in place concrete.
Typical details of precast concrete wall panel-steel column connections are shown in Figure 7.
Dowels,1/4 in. in diameter form the precast wall panels, and 1/2 in. diameter studs welded to the steel columns, are extended into the poured in place concrete.
These dewels, studs, and. field weldings of steel inserts provide positive anchorage for all four sides of the precast wall panels.
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LAYOUT OF STRUCTURAL WALLS IN BUILDING 102 I
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PRECAST CONCRETE WALL PANEL CONNECTIONS AT STEEL COLUMNS IN BUILDING 102
14 The 8 in, concrete block walls are vertically reinforced with two #4 bars at 48 in. spacing.
The cells with reinforcement are grouted with concrete.
Oowels which connect the floor slab to the block walls are #4 at 16 in. on centers.
These dowels extend into the walls 16 inches.
Positive connection of concrete block walls to intersecting walls and to the structural steel columns is specified.
At the top of the 8 in. block walls, anchor studs are provided at vertical reinforcing locations.
The studs provide 4
anchorage of the block wall to the concrete, the structural steel framing, or the roof deck. The top blocks are split to allos filling with grout at the stud locations.
Typical anchorage details of the 8 in block wall are shown in Figure 8.
The 4 in. concrete masonry walls are vertically reinforced with one #4 bar at 32 in. spa.:'ng.
Anchorage details of the 4 in. concrete block are similar to the 8 in, concrete block walls shown in Figure 8.
The RML cells are located in the high bay area (Ref. Figure 3).
They are massive reinforced concrete construction. The cell walls are 2,3, or 4 ft. thick reinforced concrete. The foundation mat is 2 ft. 4 in. thick; the roof slab is 3 ft. thick. A typical section through the cell structure is shown in Figure 9.
The cell structure extends to the basement. The entire RML cells are inside the Building 102. Because of the massive construction of th'e RML cells, damage or collapse of the Building 102 enclosure is not likely to be of consequence to the cells. The viewing windows are 30 in. x 36 in.
at each operating station. The thickness of the windowwall is 36 in.
This thickness is filled by six slabs of lead glass, each 6 in, thick.
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TYPICAL STRUCTURAL FEATURES OF RML CELLS IN BUILDING 102 (NORTH-SOUTHSECTION) s
17 Mechanical drives, gas, electrical and liquid lines are introduced into the cells through 3 in. diameter stepped holes in the wal'3.
These holes are located surrounding the viewing windows.
Special shielding plugs are used in these access holes.
The reinforced concrete floor slab over the basement is a 12 thick flat slab construction with drop panels (see Figure 10). The slab is rigidly connected to the basement walls, which are 12 in.
thick. The basement perimeter walls bear against soil except near the RML cells, where they bear against the thick RML cell walls.
The basement columns are reinforced concrete columns.
The basement floor slab is an 8 in. reinforced concrete slab on grade.
The only openings from the basement to the outside are the air exhaust duct and the stairwell.
2.
Exhaust System of Buildina 102 The exhaust system of Building 102 is of concern because the final filters and the exhaust fans for the system are located in separate Building 102A. The exhaust air of Building 102 is collected from different parts of the building and transported to building ICZA through a 60 in. diameter stainless steel duct.
If this 60 in, diameter duct is severed in a windstorm the exhaust system of Building 102 is without the benefit of the fans and the final filters, and is exposed to the atmosphere.
All glove boxes and fume. hoods in the basement area of Building 102 are exhausted through a 32 in. diameter duct that runs from the basement to the roof of the Building 102. At ambient conditions, 1
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19 the ' love boxes are maintained at a minimum negative pressure of 0.5 in. of water to prevent outleakage through small cracks or mechanical seals.
Exhaust frem the glove boxes passes thrcugh two HEPA filters in a series before it leaves the basement. The HEPA filters are located in each glove box and in the main header of the basement laboratory.
Each of these filters have an efficiency of 99.97% for 0.3 um particles [6].
Due to the locations of these filters, they are not likely to be damaged unless the.~e is structural damage to the basement area.
In case of the severance of the 60 in.
diameter stainless steel duct on the roof but no structural damage to the basement area, the exhaust air from the gicve boxes will be released to the atmosphere only after passing through a series of two HEPA filters.
The exhaust air of the RML cells also passes through a series of two HEPA filters before it enters into the 60 in, diameter stain-less steel duct at the roof top of Building 102.
The locations of these two sets of HEPA filters are not clearly defined on tha drawings.
It is assumed that one set of filters are located inside the RML cells (one for each cell) and the other set of filters is at the header located between the RML roof slab and roof of the building.
Should the 60 in diameter duct be severed but the roof of Building 102 remain intact, the exhuast air of RML cells would pass through two sets of HEPA filters prior to releasing into the atmosphere.
If the roof of Building 102 is uplifted, there is likely to be severe damage to the HEPA filter located on top of RML roof slab.
Under these circumstances the exhaust air of the RML cells could be released to the atmosphere after passing through only one set of HEPA filters.
20 3.
Building 102A Building 102A houses the fans and final HEPA filters for the air ventilation exhaust system of Building 102.
The Building 102A is of the two story construction. The second story houses the final filters and the first floor houses the fans and compressors for the ventila-tion system.
The structural system for Building 102A consists of structural steel framing. Metal cladding, which is anchored with screws to the steel framing, constitutes the exterior walls. The roof is constructed of metal deck with a concrete topping.
The metal roof deck is welded to the purlins and beams using 3/4 in, diameter puddle welds.
Cross bracing is present to resist lateral wind loads on the building.
4.
Vault in Building 105 Building 105 is located north of Building 102 (see Figure 1).
The areas of concern in Building 105 are the vault and the Critical Experi-ment Facility (CEF) cell [5].
The layout of these areas of concern is shown in Figure 4.
The vault and the CEF rooms are vault-type rooms. The walls and the roof over these two rooms are reinforced concrete. A 4 ft. thick concrete wall separates these two rooms. They are not likely to sustain structural damage in a windstorm.
The walls of the cladding laboratory area are concrete block walls.
The roof system is metal decking en steel beams.
Structural and architectural detafis for Building 105 are not available.
It is assumed that concrete block and metal deck roof details are similar to the ones in Building 102.
1
21 C.
Material Properties Properties of the building materials that are significant to wind damage assessment are listed in Table I.
The table lists median values of material properties, and a range of low and high values.
The variation of material property values is assumed to be log-normal; the magnitude of the ranges of strength are based on judgment. The primary source of material property values is EDAC Task I report (3].
If material properties for building components at the General Electric VNC facility are not provided in the report such as Reference 3, the material property values are taken from the previous EDAC reports
[7, 3] to insure consistency.
In cases where material properties are not available in documents, judgments based on standard professional practice are made.
For steel and weld metals, the ultimate shear strength is taken as 1 / / 3 times the tensile strength of the material.
This relation-ship is based on the maximum distortion energy theory for ductile material [9].
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TABLE I Haterial Properties Median Range Haterial Property Value Low liigh Source Weld Metal shear strength 47 ksi 40 ksi 56 ksi EDAC Westinghouse [8]
Metal Deck tensile strength 57 ksi 52 ksi 63 ksi ASTM [15], Sweets Catalog [16]
shear strength 33 ksi 31 ksi 35 ksi Screws tensile strength 65 ksi 61 ksi 69 ksi EDAC Westinghouse [8]
Concrete compressive strength 3000 psi 2400 psi 3750 psi EDAC TASK I [3]
Hasonry compressive strength 1350 psi 1080 psi 1688 psi EDAC TASK 1 [3]
Modulus of rupture vertical 20 psi 10 psi 40 psi EDAC [7]
horizontal 40 psi 20 psi 80 psi EDAC [7]
A 307 Anchor bolts tensile strength 69 ksi 63 ksi 76 ksi EDAC Westinghouse [8]
A 325 Structural bolts tensile strength 121 ksi 109 ksi 133 ksi EDAC Westinghouse [8]
shear strength 66 ksi 59 ksi 73 ksi Grade 40 reinforcing steel yeild strength 47 ksi 42 ksi 52 ksi EDAC TASK I [3]
Structural steel tensile yield 37 ksi 35 ksi 39 ksi EDAC TASK I [3]
23 III. STRUCTURAL RESPONSE AND DAfMGE CONSEQUENCES The effect of wind loads on a building and its components is referred to as structural response.
Tnis section presents a generic discussion of structural response and damage consequences.
In order to predict damage to glove boxes containing plutonium as well as to filters, the structural response of the building and its components due to three effects of windstorms, namely, wind, atmospheric pressure change (only in case of tornadoes), and windborne debris need to be evaluated. The wind and atmospheric pressure change effects may be combined under specific circumstances.
The general analytical approach for determining a threshold value of windspeed that will croduce significant damage to the building or its components is presented in this section.
In addition discussions concerning damage due to wind-borne debris and the effect on filters due to the failure of the air exhaust system are also presented. The structural damage to the building and its components is then translated into subsequent damage to glove boxes and filters.
Because the consequential damage to glove boxes and filters is random, subjective rather than quantitative judgements regarding glove box and filter damage are 6.ade.
Fire, as a consequence of windstorm damage, does not apoear to be a pertinent hazard.
In more than 30 major windstorm events inves-tigated by the authors, not a single one produced a fire as a consequence of windstorm damage.
24 A.
Threshold Windspeeds to produce Damage Threshold values of windspeed to produce damage to a building and its components are obtained by applying basic techniques of structural analysis These techniques were utilized by the authors to determine windspeeds in tornadoes [10].
Damage, as used here, implies the removal of a component due to outward acting forces or the total collapse of a member due to outward or inward acting forces.
Wind interacts with a flat-roofed building and produces inward acting external pressures on the windward wall and outward acting external pressures on the sidewalls, the leeward wall, and the roof (Ref. Figure 11).
In addition, relatively high outward acting exter-nal pressures are produced on locali:ed areas at wall corners, roof corners and eaves (Ref. Figure 11).
In cases where there are openings in the walls or the roof of a building, internal pressures are also produced.
These internal pressures may combine with external pressures to produce a more severe loading condition on a building component.
Since wind can come from any direction, the failure mode of a building component should be evaluated for the inward acting pressures as well as the outward acting pressures.
Knowing the strengths of the materials and the type of struc-tural system, principles of mechanics are applied to determine structural response and the wind pressure to produce a postualted failure. The structural response of a building component is made up of a static and a dynamic part.
For low-rise buildings and relatively stiff com-ponents the contribution of the dynamic part of the response can be i
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26 neglected.
The fundamental frequencies of low-rise buildings or their ccmponents such as masonry walls or metal roof decks have fundamental frequencies greater than 3Hz, while most of the free field wind gust spectrum energy is in the frequency range that is less than 0.5 H:
[11,12]. The disparity between fundamental frequencies of building components and gust frequencies of the wind suggests that the dynamic part of tne response is negl.gible for ordinary structures.
Once the wind pressure required to produce the postulated fail-ure mode is obtained, the corresponding windspeed V is calculated using appropriate equations that relate windspeed to aerodynamic pressure.
The general form of the equation is 2
p = 0.00256V C (1) where p is the wind pressure in psf V is the windspeed in mph C is a shape factor or pressure coefficient.
Equation (1) is the stagnation pressure multiplied by an appropriate pressure coefficient.
pressure coefficients are obtained primarily from wind tunnel tests of model structures.
Coefficients from the American National Standards Institute Standard A58.1-1972 [13] are used in this study.
The ANSI A58.1 Standard D J] defines three types of pressure coefficients:
(1) External pressure ccefficient, Cp (2)
Internal pressuce coefficient, C p3 (3) Net pressure coefficient, C f
27 External pressure coefficients are applicable for external wind pressures actini on enclosed buildings.
The equation for externally acting wind pressure is:
p = 0.00256V2 (C )
(2) p If the building has windows, doors or other openings that allow the wind to get inside the building, internal pressures act on the walls and roof in addition to the external pressures.
The equation for combined external and internal wind pressure acting on a building component is:
p = 0.00256V2 (C
-Cp)
(3) g p
The sign of the internal pressure coefficient C is a function of pg wind direction and opening locations in a given building.
Net pressure coefficients are used for structures such as chim-neys or towers.
The wind pressure is the net horizontal pressure and is obtained from the equation:
p = 0.00256V2 (C )
(4) f With knowledge of the wind pressure p calculated from structural mechanics procedures, and with appropriate pressure coefficients determined from the literature, the threshold windspeed V can be
~
calculated utilizing the above equations.
The threshold windspeeds that produce damage as detemined using the above equations include wind gusts.
The calculated
28 windspeeds are equivalent to " gust speed" given in Column B, Table 14 or " tornado windspeed" given in Column C, Table 14 of Reference 2.
Whether the threshold windspeeds are straight-line winds or tor-nadic winds depends on the probability of occurrence of that intensity wind.
3.
Atmospheric Pressure Change (APC)
If a tornado is the windstorm hazard, then the effect of atmospheric change (APC) may also contribute to the damage. A region of riduced pressure exists near the core of a tornado. As the tornado passes over a building the pressure inside a building becomes greater than that on the outside, thus producing a differential pressure across the walls and the roof of the building.
Table II gives the APC values associated with tornadic windspeeds for different probabilities of occurrence at the General Electric VNC facility. The probabilities of occurrence of tornadic windspeeds at the General Electric VNC facility are obtained from reference 2.
The APC values are calculated using the cyclostrophic equation (2].-
If a building is sealed, it will experience the effect of APC as the tornado passes over it. However, most industrial buildings are not totally sealed (air tight).
If there are enough openings in the walls or the roof to allow air inside the building to escape, the differential pressure will be equalized.
The venting areas cer cubic ft. of building are given in Table II for different values of APC.
l l
l
TABLE 11 Tornadic Windspeeds. Atmospheric Pressure Change and Venting a
h c
d Probabilities of Straight Line Tornadic Atmpspheric Pressure Venting Arca Occurence per year Windspeeds, mph Windspeed, mph so.ft/cu.ft change, psf 10 47
-I 10 59
-2 10 66 10-3 74
-4 10 83
-b 10 90
-6
-4 10 122 49 0.69 x 10 10 170 104 5.21x10-3
-7
-8
-3 10 235 181 0.50 x 10 8 Includes gusts; Column B of Table 14 from Reference 2 b Column C of Table 14 and Figure 4 from Reference 2 i
c Determined using cyclostrophic equation Reference Vol.11 [4]
d Escaping air is limited to 25 mph
a 30 C.
Combination of Wind and Atmospheric Pressure Change (APC)
For buildings which are sealed, the combined effects of wind and atmospheric pressure change may produce the most critical loading condition on the building components.
The highest load could be due to outward acting pressure caused by the maximum windspeed in a tornado and the associated atmospheric pressure change at the location of the maximum windspeed.
It is possible to express the value of the atmo-spheric pressure change in terms of maximum windspeed if certain assumptions are permitted.
This information is given below.
The maximum windspeed, V, in a tornado is a combination of the tangential, V and translational, V windspeeds:
g tr Y"Yt+Ytr Fujita [2] assumes that translational windspeeds is 20% of the maximum windspeed, hence V = 0.8V t
The cyclostophic equation suggests that atmospheric pressure change at the point of maximum windspeed in a tornado is:
2 APC = 0.5 a Vt Where o is mass density of air.
The total outward acting pressure due to combined effect of wind and APC on a building comconent would be 2
2 p = 0.00256V C + 0.5 o V p
31 Substituting the value fer o and utilizing V = 0.8V, the total outward t
acting pressure will be p=V2 (0.00256C + 0.00164) p The value of C would depend on the type of ccmponent such as side wall, p
roof, roof corner, etc.
For example, the pressure coefficient for the roof is C = 0.7, hence the uplift pressure would be p
2 p = 0.00343V A threshold value of a tornadic windspeed can be determined that would fail a building cceponent.
Two requirements are essential to consider combined effects of wind and APC; they are (1) the building is sealed, and (2) the threshold windsoeed is in tornadic windspeed range as spe-cified in Table II.
D.
Numerical Example An example of numerical calculations is presented to illustrate the method used in obtaining the threshold value of tornadic windspeed.
The example is uplift of the basement roof slab.
The calculations shown are for one of the postulated failure modes;other failure modes have to be considered to determine critical threshold windsceed value.
Threshold windspeed is to be determined for the roof slab shown in Figure 12.
The slab is connected to the column by 6-#9 reinforcing bars.
Four modes of failure are postualted:
1.
Failure of slab-column connection in tension due to uplift
32 9 /N 3 LAB
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33 2.
Failure of slab-column connection in shear due to uplift 3.
Failure of slab-wall connection due to uplift 4
Bending failure of slab due to uplift.
Threshold windspeed for postulated failure mode 1 only is calculated for illustrative purposes.
Other postulated failure modes should be considered and their threshold windspeed should be determined.
-Assumptions 1.
The superimposed load on the slab is neglected 2.
The tensile strength of the concrete is negligible.
-Loads Dead weight of 9 in slab = 113 psf
-Failure Mode The postulated failure mode requires that the uolift pressures negate the dead weight of the slab and cause the slab-column connection to fail in tension
-Calculations Since, the basement area is practically sealed the most critical loading condition is the combined effect of wind and atmospheric pressure change in a tornadic storm Total resistance to uplift = Weight of slab + Resistance provided by reinforcing steel
= (20 (20) (113) + 6 (1.0) (47000)
= 327200 lbs 2
Total uplift = [(20) (20)] (0.00256 C +0.00164)V p
2
= 1.37V
34 Equating the total uplift and the total resistance to uolift and solving for V 1.37V2 = 32700 lbs V = 488 mph E.
Windborne Debris Windstorms tend to pick up and transoort various types of loose debris.
The kinds of debris range in size from roof gravel to auto-mobiles. Most of the debris consists of objects such as sheet metal, timber from damaged houses or other light weight objects.
In a very intense tornado (windspeeds greater than 200 mph) debris can be pro-pelled to high velocities to become damaging missiles. Velocities attained by typical pieces of debris which can cause damage are shown in Table III. Missiles which impact exterior walls may not pose danger to glove box integrity or to HEPA filters if much of the missile energy is absorbed by the wall.
The basement area of the General Electric VNC facility Building 102 is covered by a reinforced concrete slab, and the other areas of concern at the facility are essentially enclosed by reinforced concrete walls. Hence, windborne debris damage is not likely to be critical at this facility.
F.
Exhaust System The ventilation air exhaust system in buildings containing plutonium is designed to pass exhaust air through a series of several HEPA filters prior to release to the atmosobere.
Should the mechanical or electrical equipment failure occur, or should the conduit carrying the exhaust air sever, there is a possiblity of
35 TABLE III Windstorm Generated itissile Velocities (14]
Missile Velocities, mph (V )
m Impact Weight Areg)
Windspeed, mph (V)
Missile (1b)
(ft 100 150 200 250 300 Timber Plank 28 0.04 70 98 124 160 2 in. x 4 in. x 15 ft Timber Plank 115 0.29 60 90 100 125 4 in. x 12 in. x 12 ft Standard Steel Pipe 76 0.067 65 85 110 3 in, dia x 15 ft Utility Pole 1490 0.99 80 100 13.5 in, dia x 35 ft Automobile 4000 20 25 45 Note 1.
Interpolation of missile velocity is reasonable and consistent with the current state-of-the-knowledge on missile generation.
36 releasing plutonium particles into the atmosphere.
The exhaust system of Building 102 at the Gener 4 Electric VNC facility is unique because the fans and mechanical equipment for the exhaust system are housed in a separate building. The conduit carrying exhaust air from one building to the other building could be severed in a windstom, thus exposing the exhaust system to the atmosahere.
Wind blowing past the. severed conduit is not likely to cause damage to the HEPA filters which are housed inside the building.
- Hcwever, passage of a tornado with reduced atmospheric pressure in the center would draw air out of the exhaust conduit and may cause da u ge to the filters. The rate of the atmospheric change would be the critical element in determining possible damage to HEPA filters.
G.
Damage Consequences The building damage and damage consequences discussion presented here are generic in nature.
Structural response, component damage and missile impact translate into damage to glove boxes, filters, or other containments of plutonium.
The consequences of building damage or missile impact to glove boxes and other containments can be catastrophic or can be negligible depending on the potential to releases plutonium.
The damage to glove boxes and the subsequent plutonium release potential are defined as follows:
Crushino of Glove Box:
If a heavy object falls on the glove box, structural memoers of the box may collapse resulting in the glove box being crushed.
This event could occur if a load-bearing wall or building frame should collapse thus allowing the roof structure to fall downward.
In this case the integrity of the glove box would be violated.
The material inside the glove box would be exposed to the atmosphere.
37 Perforation of the Glove Box:
Pieces of timber, concrete
- blocks, loose pieces of pipe or eculpment could strike a glove box causing an opening in the glove box window.
Plu-tonium stored in canisters is not likely to be released in this case, but loose material in powder form could possibly escape the confines of the glove box.
Failure of an exterior wall, could allow the wind to circulate throughout the building, causing loose objects to be thrown against the glove boxes.
Windborne debris could cause missile impact on the glove box and may cause perforation of the glove box.
Tear in Glove: The gloves are the weakest elements with re-spect to the glove box integrity.
Flying or moving debris could strike and tear a glove.
Some of the material in powder form could be pulled or blown from the glove box should the ventilation system be altered by the effects of the wind.
Containert::ed material or material in pellet form is not likely to escape.
These three definitions of glove box damage are correlated with extent of damage to the building and its components, and are shown in Table 4
IV.
Damage scenarios in Section V present actual damage consequences.
Primary HEPA filters are located inside the glove boxes and the RML cells in the General Electric VNC facility.
Exhaust vent piping extends from primary filter to a second set of HEPA filters housed 4
inside the building enclosure. A third and final set of HEPA filters are located in a separate mechanical building.
Damage to second and third set of HEPA filters could occur if the building enclosuru are breached.
4
TABLE IV.
Damage Consequences Building or Conoonent Damage Glove Box or Filter Danage Remarks 1.
Mechanical equipment on Filters in ventilation roof topples but does equipment crushed not penetrate roof 2.
Collapse of ucchanical Glove box crushed under Only the box underneath the equipment through roof equipment; filters crushed equipment danaged 3.
Uplif t of small portion Perforation of a few glove Items may fall through roof of roof corner or eave boxes; a few filters crushed opening 4.
Uplift of entire roof Perforation of a few glove items nay fall through opening deck boxes; a few filters crushed S.
Failure of doors or Tear in several gloves; Wind and windborne debris cause windows glovebox close to opening damage nay be perforated, a few filters outside of boxes crushed 6.
Wall corner failure Perforation of glove boxes located near the wall corner 7.
Loss of wall siding Filters crushed; perforation Windborne debris can enter the of a few glove boxes building 8.
Outward collapse of Filters crushed; perforation Windborne debris can enter the non-loadbearing wall of a few glove boxes building 9.
Inward collapse of non-Glove boxes in the vicinity of M
loadbearing masonry wall walls crushed; filters crushed 10.
Collapse of loadbearing wall Glove boxes crushed; filters Roof callapses downward crushed 11.
Lateral collapse of Glove boxes crushed; building filters crushed
39 IV.
THRESHOLD WINDSPEEDS AND FAILURE MODES The threshold values of windspeed that cause failure of building components have been calculated.
Details of calculations are con-tained in Volume II of this report (4].
Each postulated failure made has potential to damage glove boxes and HEPA filters. The failure mode that occurs at the icwest windspeed is the critical failure mode for a given building component.
Critical failure modes of all components and their associated windspeeds are sunnarized in this section.
These data are then used to formulate damage scenarios in Section V for selected windspeeds and associated probabilities of occurrence.
Calculated threshold windsceeds are considered gust speeds or tornadic windspeeds which include gusts.
In addition the threshold wind-speeds are also considered nominal windspeeds since they are based on median strengths of materials.
Windspeed ranges are provided for each calculated threshold windspeed for critical failure mode to reflect variation in material properties.
In cases where material properties are not the governing criteria for failure, windspeed ranges are based on subjective engineering judgements. All windspeed ranges are assumed to have a log-normal distribution.
Critical failure modes, damage due to wind pressures and atmospheric pressure change effects and missile impact damage are described below.
A.
Damage to Building 102 Building 102 has two floors, a partia' basement and a ground floor above the basement. Based on function, the ground floor can be divided into two areas, an office area and a laboratory area.
The laboratory
i 40 area ccntains the areas of concern on the ground floor, the RML cells and the PAL Chem Lab.
Additional areas of concern are in the basement a rea.
Section II gives the construction details for these areas.
The office area on the ground floor of Building 102 has exterior walls constructed principally of glass panels.
These panels ara assumed to be designed for wind pressure of 20 psf with a factor of safety of 1.7.
The interior walls are primarily gypsum board on 2 x 4 in. studs. These interior walls offer little resistance to a
the extreme winds which may circulate inside the building when the exterior wall panels fail.
The office area and the laboratory area are separated by a protective wall. The protective wall is a reinforced concrete masonry block wall. The wall is anchored to the steel frame on the top and to the floor slab on the bottom.
The laboratory area has 6 in. thick precast concrete exterior wall panels.
These wall panels are anchored to the steel frame on the top and sides, and to the floor slab on the bottom.
Extension of the exterior wall above the precast panels in the High Bay area (RML cells location) is constructed of metal siding anchored to the steel frame.
The anchorage system for metal siding is assumed to be self tapping screws.
The interior walls in the laboratory area are of gypsum board on 2 x 4 in studs or reinforced concrete masonry blocks. The concrete masonry block walls are anchored to the steel frame and to the floor slab.
Overhead and standard size doors to the outside are located primarily in the north wall of the laboratory area. Their failure would allow wind to circulate inside the laboratory area.
41 causing internal pressure to develop.
The roof over the office and laboratory area is a built-up roof on metal deck which is welded to the supporting steel members.
The truss which supports the 60 in. diameter (actual shape is oblong) exhuast air duct between Buildings 102 and 102A can be over-turned at a calculated nominal threshold windspeed of 73 moh.
The overturning of the truss will severe the air duct, exoosing the pre-filtered exhaust air from Building 102 to the atmosphere.
"a consequences of this failure are discussed in the section tjamage to Exhaust of Building 102.
Calculated threshold windspeed values for critical failure modes for components of Building 102 are sumarized in Table V.
The exterior glass wall panels in the corners of the office area could fail at nominal threshold windspeed of 82 mph.
The wall panel failures in the corners provide adequate venting for the office area; APC effects associated with tornadic winds need not be considered for the office area.
The combination of internal and external wind pressures are the controlling loading mode for the components in the office area.
This combination of pressures could fail the glass panels in other wall areas at a nominal threshold windspeed of 94 mph.
The doors to the exterior in the laboratory area could fail at a nominal threshold windspeed of 109 mpn.
The precast concrete exterior wall panels in the northeast corner of the building could fail at calculated nominal threshold windspeed value of 147 mph.
The controlling failure mode for the concrete wall panel is bending l
failure with the development of yield lines.
The concrete panels in
TABLE V TilRESHOLD WINDSPEEDS FOR DAMAGE TO BUILDING 102 Nominal Threshold Windspeed Range, mph Building Component Windspeed,uch Low liigh Remarks Wall glass panels in 82 57 118 Based on assumed strength corners Wall glass panels in 94 66 133 Based on assumed strength other areas Wall concrete panels in 147 131 164 Bending failure corners Wall concrete panels in 200 179 224 Bending failure other areas Wall netal siding in 191 160 218 pullout of screws corners Doors to the exterior 109 103 115 Based on assuned strength Interior protective and 133 94 188 Bending failure other walls Roof corners 109 106 112 Shear failure of netal deck around weld Roof caves 138 134 142 Shear failure Entire roof 202 196 208 Shear failure Floor slab over basenent
>235 Slab is able to resist loads including collapse of the building RML Cells
>235 Massive construction is able to resist expected loads Truss supporting exhaust 73 67 80 Overturning of truss air duct e
o 43 other wall areas could fail at calculated nominal threshold windspeed of 200 mph.
The metal siding located in the High Bay area could fail in wall corner area at calculated nominal threshold windspeed of 191 mph.
The critical failure mode for the metal siding is pulling out of the screws.
The metal siding located in wall areas other than near wall corners is not likely to fail under the pressures of exoected wind-speeds.
Failure of exterior wall panels permits wind to circulate around the laboratory area; intensity of wind circulation would depend a
on the size of openings to tne exterior. Wind circulating inside the building could collapse interior walls and damage piping and equipment.
The interior protective and other walls could collapse at calculated nominal windspeed of 133 mph.
Metal deck in roof corner areas, approximately 14 ft. x 14 ft.
could be uplifted at calculated ncminal threshold windspeed of 109 mph. The roof decking in eave areas, approximately 14 ft. wide strips, could be uplifted with the nominal threshold windspeed of 133 mph.
": Mare of metal deck in shear around the weld is the critical failure mode for the roof. Metal deck in other parts of the roof could be uplifted at calculated nominal threshold windspeed of 202 mph.
Open-ings in the roof eave areas would permit wind to circulate inside the building.
In the High Bay area, the circulating wind could damage HEpA filters located on top of the RML cells.
The RML cells are of massive construction.
The structural in-tegrity of the cells is not likely to be breached under the pressures of expected wind:peeds. The equipment located outside the cells may be l
damaged but the plugs, which hold the equipment inside and outside the
44 s
cell together, are not likely to be damaged or blown out.
Missile perforation of the cell is unlikely due to the thickness of the walls, roof, and windows.
The effects of APC on the RML cell ventilation system is, described in the next secticn, Damage to Exhuast System of Build lng102.
The roof slab over the basement area (floor slab for the ground floor) is a 12 in. flat slab with drop panels. The exterior walls of the basement area are reinforced concrete.
Positive anchorage between the' walls and floor slab is provided.
The outside of the exterior walls is covered by dirt backfill.
The interior walls in the basement area are constructed of reinforced concrete and reinforced cencrete j
masonry blocks.
The basement is virtually sealed with minimum openings to the upper level.
These openings being an elevator shaft and a stair well leading to the first floor.
The areas of concern in the basement area ar'e not likely to sustain any damage for the expected windstorm. Missiles from outside are not expected to perforate the floor slab. Missiles are not likely to be generated from equipment inside the basement since, at most there can be only limited wind circulation.
The floor slab is not expected to collapse from the effects of wind, APC, or from the effects of the structural collapse of tha ground floor on top of the slab.
B.
Damage to Exhaust System of Building 102
' The exhaust air from the areas of concern is filtered through two HEPA filters in series before leaving Building 102. After the second filtration the exhaust air is transported to the roof of the building.
45 Air flow from several areas of the building are combined and carried by a 60 in. diameter duct to Building 102A for the final filtration.
The 60 in. diameter air duct is supported by a bridge type truss between buildings 102 and 102A.
The truss span between the buildings is 122 ft.
The truss which supports the large diameter air duct could be overturned at calculated nominal threshold windspeed of 73 moh.
The overturning of the truss will sever the large air duct.
The severance of air duct will expose the prefiltered exhaust air frem Suilding 102 directly to the at:nosphere.
As wind damage to Building 102 increases, damage to the exhaust air piping also increases.
This damage to the piping has a negligble effect on the equipment in the basement area since the basement area, under the 12 in. floor slab, is likely to remain intact through the most severe windstorm expected for the area. The filters and piping located on the outside of the RML cells (first floor) could be damaged or blcwn away subsequent to the damage to the roof of Building 102.
If the filters located outside the RML cells are blown away, the air from the cells is still filtered once before release into the atmosphere. The filters located inside the cells are not likely to be damaged since they are protected by the structurally massive cells.
The damaged air exhaust system of Building 102 could be exposed to the atmospheric pressure change effects as a tornado passes over the building.
Fujita [2] gives the maximum rate of pressure droo of 0.11 psi per second.
This pressure drop could cause a flow rate through the filters located in the basement area of the magnitude
46 similar to the nomal operating flow rate of 1400 cfm. Therefore it is unlikely that the filters in the basement area can be sucked out if a tornado passes directly over the building.
Similar to the filters in the basement, the filters inside the RML cells are not likely to be sucked out.
C.
Damage to Building 102A Building 102A is of two story construction.
The first floor houses fans and compressors and the second floor houses the final set of HEPA filters for exhaust air of Building 102.
The structural system of Building 102A consists of structural steel framing.
Exterior walls are constructed of metal cladding which is anchored to the steel frames.
The cladding anchors are assumed to be self-tapping screws.
The roof consists of a metal roof deck covered with insulating concrete topping.
The doors in Building 102A could fail at nominal threshold failure windspeed of 109 mph.
These openings would permit internal pressures to be developed on the building components.
Some of the HEPA filters may sustain damage when the doors fail. At calculated nominal threshold windspeed of 158 mph, metal cladding wall corner area (approximately 5 ft. wide) could be stripped. The wind circulation inside the building would increase and damage to the HEPA filters could result in some filter material escaping the building enclosure.
The wall cladding in other parts of the walls could be stripped at calculated nominal threshold windspeed of 230 mph. Subsecuent to loss of wall claddir wind would blow through the building and
47 destroy the HEPA filters.
Filter material is likely to be blown out of the building enclosure.
D.
Damage to Building 105 The vault and CEF cell located in Building 105 are of massive construction. The walls and roof are reinforced concrete.
Detailed drawings of this area are not available.
However, it is judged that the area would not sustain damage of any consequence at the expected windspeeds.
Furthermore, collapse of other parts of Building 105 on top of the vault area is not likely to breach the structural integrity of the vault or CEF cell.
E.
Windborne Debris Damage Extreme winds tend to pick up and transcort various types of debris that range in size frem roof gravel to automobiles. Windborne debris is of secondary concern for Building 102. The energy which a missile may possess as it approaches this building will be dissipated upon impact with the exterior precast concrete walls. When the ex-terior walls fail, the equipment is likely to be crushed, therefore missiles entering the Chem Lab subsequent at the wall failures cause no additional damage. The RML cells are structurally massive. The walls and roof of the cells will be able to resist missile impact.
The basement area roof slab in Building 102 will be able to prevent missile perforation.
In addition it is unlikely that there will be any significant wind circulation in the basement area, therefore generation of missiles from equipment housed in the basement area is unlikely.
48 Perforation of Building 102A by windborne debris is of secondary concern.
Filters housed in Building 102A could be damaged at wind-speeds below which missiles are likely to be generated. The additional damage of filters due to impact of windborne debris is judged to be of minor consequence in comparison to the filter damage caused by the circulation of wind inside Building 102A.
Missile impact damage to the vault area of Building 105 is un-likely. The vault area is structurally massive, similar to the RML cells, and the energy possessed by the missile would be dissi;3ted upon impact with the roof or the walls.
F. Summary of Failure Modes Calculations of threshold values of windspeed that cause damage due to wind and atmospheric pressure change effects suggest folicwing sequence of failure modes:
73-90 moh: The bridge truss which carries the exhaust air duct between buildings 102 and 102A is likely to topole and the air duct will be severed. Also, the glass panels in the office area of Building 102 would sustain some damage.
109 meh:
In Building 102 the overhead and standard doors could fail. Also the roof deck in the corner areas of the lab building including the high bay area (over RML cells) could be uplifted. Wind is likely to circulate inside the building.
In Building 102A the doors could fail. Wind could circulate through parts of the building and damage some filters.
133-158 mph:
In Building 102 the roof panels in the eave areas in 14 ft. wide strip could be uplifted.
The precast wali panels at the wall corners could fail. The protective wall which separate lab and office areas could also fail.
These failures would permit considerable circulation of wind inside the building causing collapse of some of the l
l
49 interior walls and damage to equipment on the first floor.
In Building 102A wall cladding at the corners (about 5 ft.
wide) of the building could be stripped.
Wind circulation inside the building could damage some filters.
190-230:
In Building 102 most of the exterior wall panels are likely to fail. The roof deck in large areas of the building are likely to be uplifted.
These failures would permit wind to essentially blow through the ground floor of the building causing damage and destruction of equipment.
The basement area of Building 102 is protected by the flat slab.
It is not likely to collapse.
The RML cells are massive and are capable of resisting wind and ApC effects beyond windspeed value of 235 mph.
The equipment that is penetrating out of the RML cell walls and roof through small holes could be damaged.
But the pressures on the plugs of these holes is relatively small, hence the plugs are likely to remain intact.
In Building 102A most of the wall cladding is likely to be stripped. The filters housed on the second floor are likely to be destroyed and filter material is likely to be blown out of the building enclosure.
L
50 V.
DAMAGE SCENARIOS Damage scenarios for selected probabilities of occurrence of windspeed are formulated frcm the calculated threshold windspeeds presented in Section IV.
The damage scenarios are used for sub-sequent identification of source terms.
Four damage scenarios for selected windspeed values are presented to formulate a trend of increasing damage with reduced probability of occurrence.
Fujita [2] developed the relationship between windspeed values and their probability of occurrence at the General Electric Company VNC facility. The values used here and presented in Table II are taken from curves 3 and C of Figure 4 in Reference 2.
The wind-speed values are gust speeds in case of straight line winds and maximum tornadic windspeeds in case of tornadoes.
Damage causing threshold wind-speeds are either gust speeds or maximum tornadic windspeeds. Since damage is based on median material strengths, the threshold windspeeds are termed nominal windspeed.
Variation in material properties or sub-jective engineering judgement based on type of damage establishes windspeed range for each damage scenario. These windspeed ranges may be used to provide error bands on potential damage to the facility.
A.
Damage Scenario for Nominal Windspeed of 95 moh Probability of Occurrence: 3 x 10-6 Windspeed Range:
67 mph to 134 mph based on failure of the glass panels and the overturning of the bridge truss.
Building 102 l
Office Area: The glass exterior wall panels could fail.
Winds could circulate through the area resulting in the collapse of some partition 1
51 walls.
The protective wall which separates the office area and the laboratoryarea is not likely to sustain structural damage.
First Floor Laboratory Area: No damage of consequence.
Basement Laboratory Area: No damage of consequence.
Exhaust Air Handling System: The bridge truss that supports the 60 inch diameter exhaust air duct between Buildings 102 and 102A could overturn.
The air duct would be severed.
The air handling system in Building 102 could be exposed to an atmospheric pressure change (APC) of 29.5 psf at a rate of pressure drop of 2.5 psf /second.
Building 102A: No damage of consequence.
Vault in Building 105: No damage of consequence.
B.
Damage Scenario for Nominal Windspeed of 135 mph Probability of Occurrence:
6 x 10-7 Windspeed Range: 95 mph to 191 mph based on failure of masonry walls.
Building 102 Office Area:
Failure of most of the exterior wall panels and uplift of the roof panels in the corner areas (14 ft x 14 ft) would allow wind to circulate in the office area. Many partition walls are likely to collapse. A portion of the protective wall which separates the office area from the laboratory area could fail.
Collpase of the protective wall would allow wind to circulate into the laboratoryarea through the office area.
o 52 First Floor Laboratory Area:
Roof panels in the corner areas (14 ft x 14 ft) of the building could be uplifted.
The doors in the north, south, or east walls could fail. Wind would blow through the openings provided by the door failures and the failure of the protective wall.
The 4 inch reinforced concrete masonry wall and the gypsum partition wall of the PAL Chemical Lab could be damaged.
Equipment located in the lab could sustain some damage; the number of pieces of equipment sustaining damage may be one-tenth with estimate of upper and lower bound values of one-eight and one-twelfth, respectively.
The filters located on top, but outside, of the RML cells could sustain some damage.
Best estimate of number of filters sustaining damage is one-third as median value with estima ta of upper and lower bound values being seven-sixteenths and one-fourth, respectively.
Equipment outside of the RML cells, but attach-ed to the cell wall, might sustain damage but, the plugs which anchor the equipment to the walls are likely to remain inplace.
The RML cells will not sustain structural damage.
Basement Laboratory Area: No damage of consequence.
Exhaust Air Handling System: Through the 60 inch diameter air duct, the exhaust air handling system in Buildings 102 could be exposed to an APC of 60 psf at a rate of pressure drop of 7.2 psf /second.
Building 102A:
The doors in Building 102A could fail. Wind may circulate through the building.
Some of the filters may sustain damage but a significant amount of filter material is not likely to escape the building enclosure. Best estimate of number of filters sustaining damage is one-tenth for median value with upper and lower bound values being one-eight and one-twelfth, respectively.
53 Vault in Buildina 105: tio damage of consequence.
C.
Damage Scenario for flominal Windspeed of 180 mph Probability of Occurrence: 1 x 10-7 Windspeed Range: 127 mph to 255 mph based on failure of masonry walls.
Building 102 Office Area: Roof panels along the eaves (14 ft wide) could be uplifted and most of the exterior wall panels could fail.
The vast majority of the partition walls are likely to collapse.
The protective wall which separates the office area frem the laboratory area is likely to collapse.
First Floor Laboratory Area:
Roof panels along the eaves (la ft wide) of the building could be uplifted.
The precast concrete wall panels in corner areas (approximately 14 ft, wide) could collapse. Wind circulation through the laboratory area would increase.
All
.ie walls including the 8 inch reinforced concrete masonry walls surrounding the PAL Chem Lab could collapse.
Some of the equipment in the PAL Chem Lab is likely to be crushed.
Best estimate of number of pieces of equipment crushed is one-half as median value with upper and lower bound values being two-thirds and three-eights, respectively.
Filters on top, but outside of the RML cells could be disconnected and displacement.
Best estimate of number of filters disconnected is three-fourths as median value with upper and lower bound values being one (all) and nine-sixteenths respectively.
Equipment outside of the RML cells, but attached to the cell walls, could be disconnected but, the plugs which anchor the equip-ment to the walls are likely to remain in place.
The RML cells will not sustain structural damage.
o l
54 i
Basement Laboratory Area: No damage of consequence.
l l
Exhaust Air Handlina System: Through the severed 60 inch diameter air duct, the exhaust air handling system in Building 102 could be ex-posed to an APC of 106 psf at a rate of pressure drop of 17 psf /second.
Buildina 102A: Cladding in the wall corners (5 ft, wide) could be stripped.
Wind circulation through the doors and wall openings could disconnect and displace some filters.
Best estimate of number of filters disconnected is one-third as median value with upper and lower bound values being seven-sixteenths and one-fourth, respectively.
Some filter material could escape the building enclosure.
Vault in Buildino 105:
No damage of consequence D.
Damage Scenario for Nominal Windspeed of 230 mph Probability of Occurrence: 0.5 x 10-0 Windspeed Range: 163 mph to 325 mph based on failure of masonry walls.
Building 102 Office Area: This area is likely to be destroyed.
First Floor Laboratory Area: The precast concrete wall panels could fail and the entire roof could be uplifted. The collapsing walls would j
crush all the equipment in the PAL Chem Lab. Wind blowing through the l
laboratory area could disconnect and displace all the filters on top, but outside, of the RML cells.
Filter material could be blown out of the building enclosure.
Equipment outside of the RML cells, but attached to the cell walls, could be disconnected but, the plugs which anchor the i
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55 equipment to the walls are likely to remain in place.
The structural integrity of the RML cell is expected to remain intact.
Basement Laboratory Area: No damage of consequence.
Exhaust Air Handlina System:
Through the severed 60 inch diameter air duct, the exhaust air handling system in Building 102 could be exposed to an APC of 173 psf at a rate of pressure drop of 35.7 psf /second.
Buildina 102A: Most of the wall cladding could be stripped. Wind bicwing through the building could destroy all the filters. Most of the filter material would be blown out of building enclosure.
Vault in Buildina 105: No damage of consequence.
t
56 VI.
REFERENCES 1.
Ayer, J.A., and W. Burkhardt, " Analysis of the Effects of Abnormal Natural Phenomena on Existing Plutonium Fabrication Plants," United States Nuclear Regulatory Commission, Washington, D.C.,1976.
2.
Fujita, T.
T., Review of Severe Weather Meteorolocy at General Electric Comoany, Vallecitos, California, a recort sucmitted to Argonne National Lacoratory under Contract Number 31-109-38-3731, May 1977, 24 p.
3.
Engineering Decision Analysis Company, Incorporated, Structural Con-dition Documentation and Structural Cacacity Evaluation of the General Electric Vallecitos Nuclear Center at Vallecitos Nuclear Center at Vallecitos, California for Earthquate and Flood, Task I Structural Condition, a report prepared for Nuclear Test EngineerGig Division, Lawrence Livermore Laboratory, Livermore California, 2400 Michelson Drive, Irvine, California 92715, November 1977.
4.
Mehta, K.C., J.R. Mcdonald, and O. A. Smith, Resoonse to Structures to Wind Hazard at the General Electric VNC Facility Vallecitos, California. Volume II (Calculations), Institute for Disaster Research, Texas Tecn University, Lucoccx, Texas, July, 1979.
5.
- Mishima, J., NRC Analysis of the Effect of Natural *henomena ucon Ooerating Plutonium Plants--Features observed in the Advanced Fuel Laboratory Facilities at General Electric's Vallecitos Nuclear Center, a report submitted to USNRC, Batelle Pacific Nortnwest Laboratories, Richland, Washington, December 1977, 8 pp.
6.
General Electric Company Nuclear Energy Division, Environmental Infor-mation Report for Soecial Nuclear Material, NE00-21158, San Jose, California, Decemoer 1975, p. 5-6.
7.
Engineering Decision Analysis Company, Incorporated, Structural Con-dition Documentation and Structural Cacacity Evaluation of the Babcock and Wilcox Facility at Leechburo, Pennsvivania for Earthquake and Flood, Task 15tructural Condition, a report prepared for Nuclear Test Engineering Division, Lawerence Livermore Laboratory, Livermore, California, 2400 Michelson Drive, Irvine, California 92715, July 1977.
3.
Engineering Decision Analysis Company, Incorporated, Structural Con-l dition Documentation and Structural Cacacity Evaluation of the West-ingnouse Facility at Cheswick, Pennsylvania for Earthouake and Flood, Task I Structural Condition, a report prepared for Nuclear Test Engineering Division, Lawrence Livermore Laboratory, Livermore, California, 2400 Michelson Drive, Irvine, California, 92715, Sep-tamber 1977.
9.
Higdon, Ohlsen, Stiles, Weese, and xiley, Mechanics of Materials, Third Edition, published ny John Wiley & Sons, Incorporated, Somerset, N.J.,1976, 4S6 pp.
)
j 57
- 10. Mehta, K. C., Minor, J.E., and Mcdonald J.R., "Windspeed Analyses of April 3-4, 1974 Tornadoes", Journal of the Structural Division, ASCE, Volume 102, Number ST9, September 1976, pp. 1709-1724.
11.
Kim, Soo-II, Uolift Wind loads on Flat Roof Area, a Ph.D. Disser-tation, Department of Civil Engineering, Texas Tech University, Lubbock, Texas, August 1977.
- 12. Morris, Nicholas F., Wind Effects on Air-Succorted Structures, Preprint 2860, ASCE Spring Conver. tion and Exhibit, New York, N.Y.
April 25-29, 1977.
- 13. American National Standards Institute, Building Code Recuirements for Minimum Design Loads in Buildings and Other Structures, ANSI A58.1-1972, 60 pp.
14.
Design Gu1delines for Wind Resistant Structures at the Arconne National Laboratory Site, Institute for Disaster Researen and Department of Civil Engineering, Texas Tech University, Lubbock Texas, 1975, 68 pp.
~
15.
1971 Annual Book of ASTM Standards, Part 4, Structural Steel: Concrete Reinforcing Steel; pressure Vessel plate; Steel Rails, Wheels, and Tires, Searing Steel; Steel Forgines, American Society for Testing and Materials,1916 Race Street, Philadelphia,19103.
16.
Sweet's Architectural Catalog File, published by McGraw-Hill i
Information Systems Company, 330 West 42nd Street, New York, New York, 10036, 1970.
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