任意超越概率的地震作用确定方法

摘要

The values or the calculation methods for seismic actions with very low exceeding probabilities have not been presented in current seismic design specifications.However,a high seismic fortification level needs to be considered for some particularly important structures.To solve this problem,a conversion formula between the PGA and basic intensity was deduced,and the piecewise extreme-value type Ⅲ curves were used as the CDF for intensity.Then the PGA of an arbitrary exceeding probability can be determined by taking intensity as the intermediate variable.%现行抗震设计规范未给出极低超越概率地震作用取值或计算方法，而特别重要的工程结构已经提出了更高的抗震设防水准。针对该问题，以现行抗震设计规范为依据，回归了地震动峰值加速度与基本烈度的换算公式，用分段极值Ⅲ型曲线拟合了烈度的概率分布函数，进而给出了以烈度为中间变量，确定任意超越概率的地震动峰值加速度的方法。