An overview of the proposed guide for seismic qualification of PHWR based Nuclear Power Plant systems

This safety guide is being prepared as a part of AERB's programme for establishing design safety guides relating to Nuclear Power Plants (NPPs). Seismic qualification of structures, systems and components has always been a controversial subject during regulatory review. It is hoped to bring clarity to the regulatory requirements for designing civil structures, mechanical equipment and piping against earthquakes. This paper describes the following major issues addressed in the guide. Soil-structure interaction resulting in modification of ground motion and structural response, up life of foundation due to seismic bending moment, use of artificial spectrum compatible time histories. decoupling criteria, equivalent static method, special topics including tanks containing liquids, seismic, re-evaluation of existing plants which require special treatment seismic qualification by testing, seismic instrumentation, minimum contents of seismic qualification report. (author)