The state-of-the-art for seismic design of nuclear power plants - an assessment

Applied Nucleonics Company (ANC) has recently completed an independent assessment of the state-of-the-art of seismic design. This work has been based on the experience of ANC personnel in the field as well as the efforts of many specialists from industry and government. Besides the state-of-the-art evaluation, ANC has delineated areas of research in seismic design and analysis which require further work. Three general areas were investigated: soils, siting and seismic ground motion specification; soil-structure interaction; and the response of major nuclear power plant structures and components. In addition, a sample of industry experts was polled in an effort to establish industry concerns. Major findings include the necessity of improving knowledge of seismicity and soil dynamic parameters; improved specification of seismic inputs used for design (the Safe Shutdown Earthquake (SSE) and Operating Basis Earthquake (OBE)) and validation of models and methods used for soil-structure interaction calculations. Also considered important are the acquisition of additional experimental and test data on equipment and structures; certain changes to Regulations and Standards; and the development of simplified design methods suitable for industry-wide application. (Auth.)