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

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.

AGENDA SCAFFOLD IN NUCLEAR PLANT SEISMIC SCAFFOLD NRC INFORMATION NOTICE 2007-29 DESIGN & ANALYSIS OF SCAFFOLD SEISMIC DESIGN REQUIREMENTS GUIDELINES FOR SEISMIC SCAFFOLD

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.

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

SEISMIC SCAFFOLD Seismic Restraint for Scaffold to Avoid Sliding

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.

DESIGN & ANALYSIS OF SCAFFOLD Striking Distance for Unrestrained Scaffolding

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

DESIGN & ANALYSIS OF SCAFFOLD Per ASCE 43-05 Newmark I Equation for sliding displacement Per ASCE 43-05 Newmark II Equation for sliding

DESIGN & ANALYSIS OF SCAFFOLD STRUDL MODEL FOR SLIDING

DESIGN & ANALYSIS OF SCAFFOLD The Base Isolation Element

DESIGN & ANALYSIS OF SCAFFOLD

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

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.

DESIGN & ANALYSIS OF SCAFFOLD

DESIGN & ANALYSIS OF SCAFFOLD

SEISMIC DESIGN REQUIREMENT

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 +0.25 LLy), SeismicX = SWEX (DWx +0.25 LLx) SeismicZ = SWEZ (DWz +0.25 LLz)

SEISMIC DESIGN REQUIREMENT

SEISMIC DESIGN REQUIREMENT

SEISMIC DESIGN REQUIREMENT

GUIDELINES FOR SEISMIC SCAFFOLD

GUIDELINES FOR SEISMIC SCAFFOLD

GUIDELINES FOR SEISMIC SCAFFOLD

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