近断层地震动下减隔震桥梁地震反应分析  

Analysis of Seismic Response of Seismically Mitigated and Isolated Bridge Subjected to Near-Fault Ground Motion

作　　者：石岩[1,2] 王东升[1,2] 孙治国[1,2] 

机构地区：[1]大连海事大学道路与桥梁工程研究所,辽宁大连116026 [2]辽宁省公路工程重点实验室,辽宁大连116026

出　　处：《桥梁建设》2014年第3期19-24,共6页Bridge Construction

基　　金：国家自然科学基金项目(51178071);教育部新世纪优秀人才支持计划资助项目(NCET-12-0751);中央高校基本科研业务费资助项目(3132014326)~~

摘　　要：为了解采用减震榫和拉索限位器的连续梁桥在近断层地震动下减震系统的减震效果,以1座(40+64+40)m高速铁路预应力混凝土连续梁桥为背景,采用结构分析软件SAP2000建立了考虑邻梁碰撞效应的动力弹塑性计算模型,通过输入具有速度脉冲特性的近断层地震动和无速度脉冲地震动进行非线性时程反应分析。结果表明:在具有速度脉冲效应的近断层地震动下,采用减震榫和拉索限位器的组合减震系统可以起到较好的减震效果,其减震率可以达到60%以上;具有速度脉冲效应的近断层地震动对减震桥梁会产生更强烈的地震反应,也更容易引起邻梁碰撞,忽略碰撞效应将会高估减震效果。To have an understanding of the seismic mitigation effect of the continuous girder bridge used with the combined seismic mitigation system of shock absorbers and cable restrainers subjected to the near-fault ground motion, a high-speed railway prestressed concrete continuous girder bridge with span arrangement （40＋64＋40） m was taken as an example, the structural a- nalysis software SAP2000 was used to set up the dynamic elastic-plastic calculation model consid- ering the pounding effect of the adjacent girders and the nonlinear time-history response analysis of the model was carried out by inputting the near-fault ground motion with velocity pulse characteristic and the ground motion without the characteristic. The results of the analysis demonstrate that under the near-fault ground motion with the velocity pulse effect, the utilization of the combined seismic mitigation system of the shock absorhers and cable restrainers can achieve good effect of the seismic mitigation and the seismic mitigation ratio can exceed 60%. The near-fault ground motion with the velocity pulse effect may cause the seismically mitigated and isolated bridge to have stronger seismic response and also may easily cause the adjacent girders to pound. The ignoring of the pounding effect will result in overestimation of the seismic mitigation effect.

关 键 词：高速铁路桥 连续梁桥 减震 减震榫 拉索限位器 近断层地震动 碰撞效应 地震反应分析 

分 类 号：U442.55[建筑科学—桥梁与隧道工程] U448.23[交通运输工程—道路与铁道工程]