ML17311A994

NEI Slides for November 8, 2017, Teleconference Concerning Tornado Missile Risk Evaluator Pilot Submittals

ML17311A994
Person / Time
Site:	Vogtle
Issue date:	11/08/2017
From:	Charkas H, Shanley L, Tegeler B, Vaughn S Jensen Hughes, Nuclear Energy Institute
To:	Office of Nuclear Reactor Regulation
Brown E DORL/LPL-LSPB 415-2315
References
EPID L-2017-LLA-0350
Download: ML17311A994 (31)

Text

TMRE Public Meeting Steve Vaughn NEI Hasan Charkas - EPRI Bret Tegeler - JENSENHUGHES Leo Shanley - JENSENHUGHES November 8th, 2017

• Teleconference 1

Agenda

• Opening Remarks

• Industry responses to a subset of NRC technical questions (ML17235B148) regarding NEI 1702, Revision 0

- Robust Targets/Missiles

- Target Characteristics

- Missile Inventory

• Path forward 2

Appendix C Questions

• Responses to Question 11 (a thru i) except 11.h (spalling secondary effect) 3

11.a

• Figure C1 and Table C1 do not appear to conclude that the assumptions are representative of plant targets. Specifically, the assumption for exhausts and stacks is described as having the exhaust/stack being supported on both ends.

Generally, and specific to the example in Figure C 1, these targets are unsupported at the end. The guidance should ensure justification is provided to demonstrate the appropriateness of this assumption.

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Response to 11.a

• Appendix C has been revised to include two cases:

Fluid filled pipe case that is supported on both ends of pipe Vent pipe case that is supported by a cantilevered support Table C6 results reflect these cases 5

11.b

• In Section C.3.1, it is the NRC staffs understanding that M should be the mass of the missile, vice the weight provided in the missile descriptions (mass = weight/32.2). For noncylindrical missiles, the guidance should ensure that the equivalent diameter used is the diameter of a circle equal to the frontal area of the noncylindrical missile.

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Response to 11.b

• We are in agreement with the staffs understanding. While missile weight is referenced in the missile descriptions, the appropriate value of mass is used when required, such when the BRL equation for steel is used :

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11.c

• The assumption that only steel missiles are capable of perforating steel targets, should be verified and a justification provided. Also, in the associated reference document that describes the equation above, it is said that the thickness of the steel barrier required to prevent perforation should exceed the thickness for threshold of perforations by 25 percent. It should be considered whether this assumption is significant enough to be added.

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Deformation Failure Mode (Local) Penetration Failure

• Appendix C approach Modes (Local) addresses both local and global effects on steel targets

• Local effects relate to penetration and deformation failures Penetration failure is assessed using BRL equation (empirical ) Deformation Failure Mode (Global)

Deformation failure is assessed using a mechanics based approach

• Global effects are related to larger deformations 9

Steel missiles considered for penetration

• Penetration into a steel plate requires the missile to have a high areal density and strength to remain intact (e.g., steel jacketed lead)

• DOE Standard 301496 recommends only using BRL equation for rigid missiles

• Thus, for assessing penetration failure, only steel missiles are considered All missiles

• However, all missiles are considered considered credible for for deformation failure modes deformation 10

11.d

• In Section C.3.1, the guidance should provide a table of values of perforation thicknesses for the different targets in question, or an example of this equation used to evaluate one of the targets.

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Response to 11.d

• The following table summarizes three example cases indicating the parameters used in the concrete perforation using the BRL equation:

1. 8 Rebar Utility Pole 4x12 timber Parameter Notes Missile Weight (lb) Ref Report Table 52 8 1500 200 1" dia 13.5" dia 4"x12" Missile Impact Face Dimensions Ref Report Table 52 2

Assumed Missile Projected Area (in ) Ref Report Table 52 0.8 143.1 48.0 Equivalent Diameter, D (in) [Based on Projected Missile Area] 1.0 13.5 7.8 Assumed Concrete Design Strength, f'c (psi) Representative 3,500 3,500 3,500 Median Concrete Strength Factor , Fm NEI 0713; Section 2.3.1 1.15 1.15 1.15 Concrete Age Factor, Fage NEI 0713; Section 2.3.1 1.20 1.20 1.20 Dynamci Increase Factor, DIF NEI 0713; Section 2.3.1 1.25 1.25 1.25 Median Concrete Strength Factor'c (psi) f'c x Fm x Fage x DIF 6,038 6,038 6,038 Vertical Impact Velocity; V vert (fps) V vert = (2/3 V hor) Ref Report Figure C3 225 179 219 BRL Equation; Report Limiting Perforation Thickness; T (in) Section C3.1 6.1 7.7 3.6 12

• Summary Table C5 reflecting results for each missile and target combination 13

11.e

• On the Variation of Impact Velocity with Missile Weight (Figure C3) plot provided shows how missile velocity assumed in this analysis varies with weight. The equation of the line provided represents the best fit line for the data (blue dotted line), but the model uses the green line, which is conservatively shifted up to a maximum velocity of 230 mph. The guidance should include the equation of the line for the green line in order to calculate any missile velocity given missile weight or vice versa.

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Response to 11.e Report will be updated to better describe green line relationship as used in the model:

Vi(W)= 0.0317W + 230.0

Where, Vi = Missile impact velocity (mph)

W= Missile Weight (lb) 15

11.f

• In section C.3.1, the assumption is that only like materials can cause perforation (steel to steel). The guidance should ensure that a justification is provided to support this assumption.

Response to 11.f

• Refer to Response to 11.c 16

11.g

• Figure C14, should be reviewed to determine whether it can be used to estimate tank rupture Response to 11.g

• This is a typographical error. Figure number should read Figure C13 17

11.i

• The data in Table C5, specifically the minimum perforation thickness in the first column, should be validated and more comprehensive guidance provided regarding the use of the Concrete Perforation equation. Additionally, the evaluations on the failure of the concrete using those values should be addressed should the validation demonstrate that the values should be changed. Similar validation efforts should be performed on vehicle impact and the tree impact evaluation.

Response to 11.i

• This issue is similar to that raised in Question 11.d 18

Responses to Appendix B and Robust Missile & Target Questions 19

5.d., 10.c., and 10.d.

• These comments refer to the development of Tables B 14 and B18

- Table B14: Robust Target Missile Matrix

• Matrix showing which missile types can damage which robust target category

• 23 missile types (1 23) vs. 9 target categories (A - I)

- Table B18: Missile Damage Capability

• Provides percentage of total missiles that can damage each robust category (A - I)

• Results repeated in Table 52

• Tables B14, B18, and others in Appendix B, were updated in NEI 1702, Rev. 1

• Table C.6 (Target Damage Approximations) has been updated but was not reflected in NEI 1702, Rev. 1.

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Table C.6 21

Tables B14 and B18 22

Use of Table C.6 Results to Create Table B14 Table B13: Table B12:

Robust Target Individual Target Categories and Descriptions and Descriptions Assigned Categories Table C.6:

Individual Target Table B14:

Damage Robust Target Missile Approximations Matrix Table 32:

Missile Types and Descriptions To next page 23

Use of Table B14 and B17 to Create Table B 18/Table 52 Table B14:

Robust Target Table B15: Missile Matrix Unrestrained (from previous page)

Missile Inventories Table B18:

Missile Damage Table 32: Table B17: Capability Missile Types Average and and Table B16: Missile Type Table 52:

Descriptions Restrained Inventory Robust Missile Missile Inventories for EEFP Inventories Calculations 24

B B R o bu st T a r g e t C a te g or y Diesel Generator Air intake (large) Diesel Generator Air intake (small)

Target Description 1 R e ba r 2 G a s C ylinde r 3 T a nk/D r um

- At least 16 diameter and thickness less than 3/8 4 U tility P o le 5 C a ble R e e l 6 3 " pip e 7 6 " pip e

• Table C.6 worst case results - damaged by all

• Category B: Steel Pipe 8 1 2 " p ipe 9 Stor a g e B in 10 C o nc r e te P a ve r Example 11 C o nc r e te B loc k but at least 0.125 12 W ood B e a m 13 W ood P la nk 14 M e ta l sidin g 15 P lyw o od Sh e e t 16 W ide Fla ng e 17 C h a n ne l Se c tio n 18 Sm a ll e q uip m e nt 19 L a r g e E q uip m e nt 25 20 Ste e l Fr a m e /G r a ting 21 missiles except: 1, 11, 13, 15, 20 L a r g e Ste e l Fr a m e

- Crushing/Crimping of > 50%

22 V e hic le 23 Tree

Example - Category B (cont.)

• Damaged by all missiles except:

1, 11, 13, 15, 20

• Results shown in Table B14 26

Example - Category B (cont.)

Missile Type Percentage 1 Rebar

• From Table B17, sum of missile 2 Gas Cylinder 0.5%

percentages (excluding 1, 11, 3 Drum, tank 4 Utility Pole 0.2%

0.1%

13, 15, 20) is 53% 5 Cable Reel 0.4%

6 3 Pipe 11%

- Majority of missiles contributing to 7 6 Pipe 0.6%

total are: 3 pipes, metal siding, 8 12 Pipe 0.1%

channel sections and trees (42%) 9 Storage bin 1.6%

- Other damaging missiles have 10 Concrete Paver 11 Concrete Block 2.7%

relatively small inventories at sites 12 Wood Beam 1.5%

13 Wood Plank 14 Metal Siding 17%

• Table B18 for Category B: 15 Plywood Sheet 16 Wide Flange 0.3%

- Calculated percentage = 53% 17 Channel Section 7.2%

18 Small Equipment 1.0%

- Final percentage rounded up to 19 Large Equipment 0.5%

55% 20 Frame/Grating 21 Large Steel Frame 0.5%

22 Vehicle 0.8%

• Table 52 for Category B: 55% 23 Tree TOTAL 6.8%

53%

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Tables B18 and 52

• Most categories get a modest reduction in damaging missiles (factor of 2 to 3)

- B, C, D, E, F, G

• Most robust targets are thick steel pipes (for crimping/crushing) and concrete roofs 28

4.f. and 5.g.

• 4.f. - Number and description of missile types in Table 32 do not correspond with missile information in other tables

- 23 missiles used in all tables except Tables 33 through 38

- Tables 33 through 38 are missiles created from the deconstruction of buildings

• Only the first 22 missiles are listed, since missile #23 is a tree

• 5.g. - Example EEFP calculations using different percentages for robust missiles than Table 52

- Corrected 29

7.b

• Section 7.4 discusses using a smaller area if target is partially shielded; the guidance should address shielding considerations for area calculations

- Section 5.3.2 discusses shielding examples and how shielding would be used to change target areas

• Targets may be adjacent to Class 1 buildings or other structures that would preclude missiles hitting targets from those directions

• Penetrations or openings may be partially blocked by piping or supports, reducing the effective opening size

- The basis for how shielding is credited in reducing target areas should be justified and documented 30

Questions?

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