基于不同设定地震方法的长周期建筑设计反应谱的对比分析

Comparison of Design Response Spectrum for Long Period Structures Based on Scenario Earthquake

现有的设定地震方法主要有两种:加权平均法和最大概率法。本文首先简要介绍了这两种方法,然后以烟台地区一高层建筑为研究对象,分别采用加权平均法和最大概率法进行地震危险性分析,确定出设定地震震级、震中距以及具体空间位置,给出了两种方法的设定地震反应谱,最后对这两种方法所得结果的差异进行了对比和分析。结果表明:加权平均法所得反应谱将长周期处的安全性考虑在内,适用于中长周期建(构)筑物;最大概率法由于其长周期处谱值偏低,会增加长周期工程的危险性,不宜用于长周期工程,但对短周期建(构)筑物应用合理;对于自振周期不同的建筑工程应选用不同的地震危险性分析方法进行设计反应谱的确定。

Two kinds of determining method for scenario earthquake are presented in this paper, namely the weighted average method and maximum probability method. This paper briefly introduces the two methods. Then taking a high-rise building in Yantai area as a case study, we use the weighted average method and maximum probability method to realize seismic hazard analysis, determine earthquake magnitude, the epicenter and specific space position, and then give two response spectrums of two methods. By comparing the differences of response spectrum between two methods, we find out that the weighted average method is more suitable for long period structures with considering the safety of long period. Maximum probability method is more suitable for short period structures. It is reasonable to choose corresponding different method when the structures have different natural vibration period.