Seismic Design Spectra for Nuclear Power Plants

Statistical studies made recently, independently by the Blume and Newmark organizations for the AEC, of a number of earthquakes are reported with a view toward developing recommendations for design response spectra to be used for nuclear power plant facilities. Recommended criteria and design spectra are reported which differ somewhat from previous recommendations but which are generally in accord with current practice. The new recommendations are more rational than previous ones in the sense that they are consistent with the results of a larger number of observations, and will generally tend to agree better with response spectrum calculations made for the same earthquake history with different levels of damping. Recommendations are also included regarding other seismic design criteria for nuclear power plants, including damping values and combination of response components.