考虑近场地震竖向效应的改进Pushover分析方法  

Improved push over analysis method with consideration of the vertical effect of near-fault earthquake

作　　者：尹犟[1] 周先雁[1] 易伟建[2] 陈伯望[1] 段绍伟[1] 

机构地区：[1]中南林业科技大学土木工程与力学学院,长沙410004 [2]湖南大学土木工程学院,长沙410000

出　　处：《振动与冲击》2015年第20期143-149,共7页Journal of Vibration and Shock

基　　金：国家林业公益性行业科研专项资助(201304504);国家自然科学基金(511781755);国家自然科学基金(51274258);湖南省自然科学基金(13JJ5027);教育部高等学校博士学科专项科研基金(20124321120006);中南林业科技大学博士后基金;长沙市科技计划项目(21597)

摘　　要：基于结构动力学理论推导两种考虑近场地震竖向效应的改进Pushover分析方法。按合理方式在结构的每个集中质量处施加竖向地震力,并据结构屈服后动力特性对其水平加载模式及形状向量进行修正。采用两种改进Pushover分析方法及两种传统Pushover分析方法,估计近场条件下两个框架结构顶点位移、楼层位移及层间位移。以算例结构在30组近场地震记录作用下的时程分析统计结果为基准,评估4种Pushover分析方法估计精度。结果表明,改进方法Ⅱ的精度最高,对算例框架最大顶点位移、最大楼层位移及最大层间位移估计结果均较准确,可用于近场条件下规则结构的地震反应分析及地震损伤评估。Based on the theory of structural dynamics,two kinds of improved push over analysis（ POA） procedures were deduced to consider the vertical effect of near-fault earthquake. In the improved methods,the vertical seismic force was supposed to be loaded on each lumped mass before the structural POA,and the lateral load distribution as well as the shape vector were modified according to the dynamical features of the structure after yielding. Applying two improved and two traditional POA procedures respectively,two frame structures in near-fault site, as numerical examples, were investigated for their important seismic responses,such as the roof displacement,floor displacement and inter-story drift.According to the statistical results of structural dynamic time-history analysis based on 30 sets of near-fault ground motion records,the accuracy of seismic response parameters estimated by different POA methods was testified. The results show that the modified method Ⅱ possesses much higher precision compared with other methods and this method can simultaneously estimate the maximum roof-displacement,maximum floor-displacement and maximum inter-story drift of frame with high accuracy,hence can be applied to the seismic response analysis and seismic damage assessment of regular structures in the near-fault site.

关 键 词：近场地震 竖向效应 PUSHOVER分析方法 

分 类 号：TU311.3[建筑科学—结构工程] TU973.23