Understanding seismic design criteria for Japanese Nuclear Power Plants

This paper summarizes the results of recent survey studies on the seismic design practice for nuclear power plants in Japan. The seismic design codes and standards for both nuclear as well as non-nuclear structures have been reviewed and summarized. Some key documents for understanding Japanese seismic design criteria are also listed with brief descriptions. The paper highlights the design criteria to determine the seismic demand and component capacity in comparison with US criteria, the background studies which have led to the current Japanese design criteria, and a survey of current research activities. More detailed technical descriptions are presented on the development of Japanese shear wall equations, design requirements for containment structures, and ductility requirements.