A Method for Estimating the Distribution of Annual Maximum Acceleration Values and Its Application to the Design Value Problems

Seismic hazard analyses at two sites located in the western part of the Chubu District in Japan

Abstract

A method for estimating the distribution of annual maximum acceleration values at two sites, which are different from each other in seismic activities, located in the western part of the Chubu District in Japan, is presented. Using two sets of seismicity data in other historical times and linking the estimators from them, these distribution curves are obtained as extreme ones with upper bound limits. The exceedance probabilities of the peak acceleration in t years are also obtained.
Subsequently, the optimum acceleration and probability of failure of the structure during service life are calculated with the aid of the minimum cost criterion, under the assumption that the structure is in one of two states after each earthquake, failure or no failure. Namely, the design values are automatically determined considering the initial construction cost and expected failure cost, related to the degree of importance of the structure and its circumferences lying around. In particular, it has been shown that the optimum probability of failure is individually constant irrespective of the duration of service life of the structure within the range of actually existing expected failure cost values, given the local seismicity and cost values.