考虑残余位移影响的梁式桥基于性能的抗震设计  

Study on performance-based seismic design for beam bridges considering residual displacement

作　　者：李宇[1] 车艳阳 王森[1] 

机构地区：[1]长安大学公路学院旧桥检测与加固技术交通行业重点实验室,陕西西安710064

出　　处：《土木工程学报》2015年第3期71-78,共8页China Civil Engineering Journal

基　　金：国家自然科学基金(51408042;51408040);陕西省自然科学基金(2014JQ7253);中央高校基本科研业务费专项资金(2013G1211006)

摘　　要：以我国现行的桥梁抗震设计规范为依据,合理地选取4类场地320条强震记录,统计出适用于我国梁式桥抗震设计的弹塑性位移谱和残余位移谱,并改进正规化累积耗能参数,得到基于损伤性能指标的等效位移延性系数,并以此对桥梁的地震损伤模型进行探讨。在此基础上,提出考虑残余位移影响的梁式桥基于性能的抗震设计方法,并给出具体算例,其非线性时程分析的结果表明:该方法综合考虑了结构的变形和耗能能力,可有效地控制桥墩的首超破坏、塑性累积损伤以及震后残余位移,适用于我国短周期、低延性的一般规则梁式桥的中、低矮桥墩的抗震设计。According to the current Chinese code of bridge seismic design,320 strong motion records of four sites are selected to establish elastic-plastic displacement spectra, residual displacement spectra. Normalized parameters of cumulative dissipation energy are improved and equivalent ductility coefficients based on damage indexes are obtained.Furthermore,developed seismic damage models are discussed. Performance-based seismic design for bridges considering residual displacement is proposed and specific examples are provided to show the detailed design procedures. The nonlinear time-history analysis results show that both deformation capacity and energy dissipation capacity of bridge can be considered by the proposed method and the maximal displacement, plastic cumulative damage and residual displacement can be controlled well. The proposed method can be applied in design of low and medium-height piers with short natural period and low ductility.

关 键 词：梁式桥 基于性能抗震设计 弹塑性位移谱 残余位移谱 非线性分析 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]