序列型地震作用下考虑损伤的强度折减系数  

Damage-based strength reduction factor for sequence-type ground motions

作　　者：张永群[1] 陈隽[1,2] 孙潮旭 

机构地区：[1]同济大学土木工程学院建筑工程系,上海200092 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《地震工程与工程振动》2016年第4期139-146,共8页Earthquake Engineering and Engineering Dynamics

基　　金：国家"十二五"科技支撑计划(2012BAJ11B02)~~

摘　　要：基于性态的结构抗震设计中的强度折减系数是确定结构非弹性反应谱的重要依据。本文研究主余震序列型地震作用下单自由度体系考虑损伤的强度折减系数谱。首先收集主余震实测记录并按中国抗震规范要求进行场地类别划分,对余震峰值进行调幅后进行单自由度结构弹塑性动力时程分析,研究了结构周期、延性系数、损伤指数、余震作用等因素对强度折减系数需求的影响。结果表明余震对强度折减系数的影响显著,考虑累积损伤的强度折减系数(R_D)是基于位移延性的强度折减系数(R_μ)的0.6至0.9倍。最后,经过统计平均和回归分析,建立了平均强度折减系数谱的简化公式。This paper investigates the strength reduction factor of single degree of freedom system subjected to the mainshock-aftershock sequence-type ground motions. Records of mainshock-aftershock earthquakes were collected and classified into four groups according to the criteria specified in the Code for Seismic Design of Buildings in China. Based on the nonlinear time-history analysis of single-degree-of-freedom inelastic systems,the effects of period,ductility factor,damage index and aftershock have been studied statistically. The results indicate that the aftershock ground motion has significant influences on strength reduction factors,and the damage-based strength reduction factor is about 0. 6 - 0. 9 times of the ductility-based strength reduction factor. Finally,the empirical expression of strength reduction factors was established by statistical mean method and regression analysis.

关 键 词：非弹性谱 损伤指数 强度折减系数 主余震序列型地震动 场地条件 

分 类 号：P315.9[天文地球—地震学]