1. GTSTRUDL User’s Group Annual Meeting - 2012
SEISMIC SCAFFOLD
June 15, 2012 Parimal Gandhi, PE
Sr. Engineer

2. PURPOSE OF SEISMIC SCAFFOLD
To provide guidelines and installation requirements
for scaffolds built in safety related areas
with regard to both personnel safety and plant equipment operability.

3. AGENDA SCAFFOLD IN NUCLEAR PLANT SEISMIC SCAFFOLD
NRC INFORMATION NOTICE
DESIGN & ANALYSIS OF SCAFFOLD
SEISMIC DESIGN REQUIREMENTS
GUIDELINES FOR SEISMIC SCAFFOLD

4. SCAFFOLD IN NUCLEAR PLANT
Temporary tube and coupler scaffolds are often used at nuclear plants for various maintenance activities.
Scaffolds are not safety related.
Scaffolds are designed for dead weight and live load.
Scaffolds are unanchored, i.e. free standing.

5. SEISMIC SCAFFOLD
In case of a seismic event, free standing scaffolds could slide, oscillate and tip over.

6. SEISMIC SCAFFOLD
Seismic Restraint for Scaffold to Avoid Sliding

7. NRC INFORMATION NOTOCE 2007-29
To alert licensees about recent operating experience at nuclear power facilities where temporary scaffolding installed to support maintenance activity has affected the operability of safety-related equipment.
The NRC expects that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar problems.

8. DESIGN & ANALYSIS OF SCAFFOLD
Striking Distance for Unrestrained Scaffolding

9. DESIGN & ANALYSIS OF SCAFFOLD
The Fundamental Frequency of Scaffolding 3.5 Hz.
Critical Damping of Scaffolding > 7%
Sliding Distance of Scaffolding for 23 sec of SSE
Oscillation of Scaffolding

10. DESIGN & ANALYSIS OF SCAFFOLD
Per ASCE Newmark I Equation for sliding
displacement
Per ASCE Newmark II Equation for sliding

11. DESIGN & ANALYSIS OF SCAFFOLD STRUDL MODEL FOR SLIDING

12. DESIGN & ANALYSIS OF SCAFFOLD
The Base Isolation Element

13. DESIGN & ANALYSIS OF SCAFFOLD

14. DESIGN & ANALYSIS OF SCAFFOLD
For Bolted Steel Structure 7% Damping SSE Horizontal Acceleration Response Spectra

15. DESIGN & ANALYSIS OF SCAFFOLD
Based on scaffold loading requirements and dimensions vertical posts, bearer, runners and braces etc. are sized from Excel Modular Scaffold Technical Manual EMSLC-TSM-1001.

16. DESIGN & ANALYSIS OF SCAFFOLD

17. DESIGN & ANALYSIS OF SCAFFOLD

18. SEISMIC DESIGN REQUIREMENT

19. SEISMIC DESIGN REQUIREMENT
Design Load = DW +LL + Seismic
Where
DW= Dead Weight of Scaffolding (Include Hand Rails)
LL = Live load 50 lbs/ ft2
SeismicY = SWEv (DWy LLy),
SeismicX = SWEX (DWx LLx)
SeismicZ = SWEZ (DWz LLz)

20. SEISMIC DESIGN REQUIREMENT

21. SEISMIC DESIGN REQUIREMENT

22. SEISMIC DESIGN REQUIREMENT

23. GUIDELINES FOR SEISMIC SCAFFOLD

24. GUIDELINES FOR SEISMIC SCAFFOLD

25. GUIDELINES FOR SEISMIC SCAFFOLD

26. Questions? Thank you. THE END Generator
Converts Mechanical energy to Electrical Energy
Rotate Electric Coils in Magnetic Field
Has a matched Turbine - Rotational Energy
Steam Turbine
Uses Steam passing over blades
Steam is used because higher available energy
Consists of 3-4 Turbines together on 1 shaft
Uses "dry" steam - no water - turbine damage
Use water hose example blasting into the ground/rock
Condenser
Converts remaining steam back to water
Supplies pumps that feed the Boiler (stm gen)
Feedwater Pumps
Feedwater Heaters
Talk about Temperatures of Fluids