一种估计重大工程场地地震危险性的新方法

A NEW METHOD OF ESTIMATING SEISMIC HAZARD ANALYSIS FOR GREAT ENGINEERING SITE

在简要回顾了地震危险性评定方法的要点之后，提出了一种评定工程场地地震危险性的新方法．这一方法的要点是：（1）用现在流行的方法对地震活动性进行统计分析和潜在震源划分，并将潜在震源简化为矩形断层模型；（2）在某一潜在震源上，一旦发生某一震级的地震，则采用强震地震学的研究结果从物理上模拟这次地震在重要工程场地引起的强地面运动；（3）在这一潜在震源上，可以构造出在预测的T年内符合震级-频度关系的一组随机地震序列，重复（2）的步骤可得到这一组地震序列发生时在重要工程场地引起的地面运动序列；（4）对于多个潜在震源，重复（3）的步骤，由统计方法可计算出在T年内场地的超越概率．因此，本文提出的方法既保留了以往地震危险性分析关于潜在震源划分、地震发生规律的特点，又充分吸收了强震地震学关于强地面运动的研究成果。

After simply reviewing the main points of seismic hazard analysis method, this paper presentsa new method to estimating seismic hazard. The basic ideas of the method are as follows : (1) theseismicity is statistically analyzed and the potential seismic sources are divided by popular method,whose potential seismic source is simplified as regular fault model. (2) Onec the earthquake withsome magnitude occurs in the potential seismic source area, the strong ground motion caused by it will bephysically modeled by using the research result of strong motion seismology. (3) In the potential sets.mic source area, random earthquake series are modeled in prediction time T years, which will correspond to the magnitude-frequency relation. If step (2) is repeated, we will obtain one random seriesof strong ground motion in great engineering site caused by the simulated earthquake series. (4) Forthe multiple potential seismic sources, after repeating step(3), we can obtain exceedance probability instudied area in given time Tyears by using statistical method. Therefore, this paper's method not onlykeeps characteristics of former seismic hazard analySis about potential seismic source zonation andearthquake occurrence law, but also absorbs research results of strong seismology about strong groundmotion.