环境温度对SMA-LRB隔震桥梁地震响应的影响  

Influence of Ambient Temperature on Seismic Response of SMA-LRB Isolated Bridge

作　　者：石岩[1] 成昭 王浩浩 刘云帅[1] 王文仙 裴银海 SHI Yan;CHENG Zhao;WANG Haohao;LIU Yunshuai;WANG Wenxian;PEI Yinhai(School of Civil Eng.,Lanzhou Univ.of Technol.,Lanzhou 730050,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050

出　　处：《工程科学与技术》2022年第3期169-179,共11页Advanced Engineering Sciences

基　　金：国家自然科学基金项目(51908265);红柳优秀青年人才资助计划(04–061810);道路与铁道工程安全保障省部共建教育部重点实验室开放课题(STKF201904)。

摘　　要：随着隔震技术的发展,隔震桥梁的服役环境日趋复杂,环境温度对隔震桥梁抗震性能的影响亟待考虑。为减小地震作用下桥梁的最大响应及残余变形,结合铅芯橡胶支座(LRB)及形状记忆合金(SMA)的优点,组合形成具有自复位能力的SMA–LRB支座。基于一座4跨SMA–LRB隔震连续梁桥,考虑SMA–LRB支座在不同环境温度下的力学特性,对不同环境温度下的隔震连续梁桥进行非线性动力时程分析,得到结构关键部位的动力响应。结果表明:LRB上加设SMA可有效控制支座的位移响应,且SMA自复位特性使其对残余位移的控制效果显著;随着环境温度的降低,LRB和SMA–LRB两种支座的峰值位移和残余位移均随之而减小,但SMA–LRB支座对位移的控制能力和自复位能力较常温有所降低;支座刚度随着环境温度减小而增大,致使桥墩墩顶位移和墩底剪力也随之增大,且较低墩的墩底剪力对温度变化更加敏感。环境温度对SMA–LRB隔震桥梁抗震性能影响的定性评估,可为该类桥梁结构的分析和设计提供借鉴与参考。With the development of seismic isolation technology,the service environment of the isolated bridge is becoming increasingly complicated,and the effect of ambient temperature on the seismic performance of isolated bridge should be considered urgently.To reduce the maximum response and residual deformation of the bridge under the action of an earthquake,combining the advantages of the lead rubber bearing(LRB)and shape memory alloy(SMA),a self-resetting SMA–LRB bearing was formed.In view of the temperature sensitivity of rubber and SMA materials,based on a 4–span SMA–LRB seismic isolation continuous girder bridge,the nonlinear dynamic time history analysis of isolated continuous girder bridges under different ambient temperatures was performed to obtain the dynamic response of the key parts of the structure,while the mechanical properties of SMA–LRB bearings at different ambient temperatures were considered.The results showed that the addition of SMA to LRB increased the horizontal rigidity and effectively controls the displacement response of the bearing.At the same time,the self-reset characteristic of SMA made the residual displacement control effective.As the ambient temperature decreases,the peak displacement and residual displacement of the LRB and SMA–LRB bearings would decrease,but the displacement control ability and self-reset ability of the SMA–LRB bearing would decrease compared with normal temperature.The stiffness of the bearing increased with the decrease of the ambient temperature,which caused an increment in the displacement of the top of the pier and the shear force at the bottom of the pier,and the shear force at the bottom of the lower pier was more sensitive to temperature changes.The qualitative evaluation of the influence of ambient temperature on the seismic performance of SMA-LRB isolated bridge can provide reference for the analysis and design of such bridges.

关 键 词：隔震桥梁 形状记忆合金 铅芯橡胶支座 环境温度 地震响应 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]