摩擦摆支座隔震铁路连续梁桥振动台试验研究  

Shaking table test on a railway continuous girder bridge with friction pendulum bearings

作　　者：邵长江[1,2] 肖正豪 漆启明 韦旺 何俊明 SHAO Changjiang;XIAO Zhenghao;QI Qiming;WEI Wang;HE Junming(College of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;National Engineering Laboratory for Technology of Geological Disaster Prevention in Land Transportation,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院桥梁系,成都610031 [2]陆地交通地质灾害防治技术国家工程实验室,成都610031

出　　处：《振动与冲击》2021年第14期292-298,306,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(51978581,51178395);四川省应用基础研究重点项目(2017JY0059)。

摘　　要：为研究地震下摩擦摆隔震支座在连续梁桥中的减隔震效果及动力行为,以某(24+32+24)m箱型等截面铁路连续梁桥为原型,进行了1/10缩尺模型的连续梁桥振动台试验。采用3组实测近场地震波进行纵竖向联合输入,观测桥梁试验中及震后损伤情况,并对桥梁位移、加速度及应变响应进行了分析。结果表明:不同近场地震下结构响应具有显著差异;随着地震波地面峰值加速度(PGA)增大,中墩纵向位移平均幅值小于边墩,且其增幅率远小于边墩盖梁;当PGA增大时,摩擦摆支座的隔震率更高,隔震效果更好;在0.5 g地震作用下中墩仅出现少量细微裂缝,纵筋最大应变为786με远小于其屈服应变,说明桥墩未屈服,摩擦摆支座可以有效降低桥墩内力响应。To investigate the isolation performance and dynamic behavior of a continuous bridge with friction pendulum bearings under earthquake,taking a(24+32+24)m continuous railway bridge with constant depth box section as a prototype,and the shaking table tests of a 1/10 scale bridge model were conducted.Three typical near-field ground motion records were selected as the input excitations,and the longitudinal and vertical waves were combinedly input.The phenomena in shaking process and post-earthquake damage were observed,the seismic responses were analyzed in terms of displacement,acceleration and strain.The results show that there are obvious differences in responses under different near-fault earthquake waves.With the increase of the earthquake wave’s peak ground motion(PGA),the average longitudinal displacement amplitude of middle piers is smaller than that of side piers,and its increase rate is much smaller than that of side piers.When the PGA is increased,the isolation efficiency and effect of friction pendulum bearing(FPB)is higher and better.Only a few cracks appear under the 0.5 g earthquake wave,and the maximum longitudinal reinforcement strain is only 786μεin the mid pier,which is far away from the rebar yielding strain,indicating that this pier is not in the yield state and the FPBs can reduce the internal force response effectively.

关 键 词：铁路连续梁桥 摩擦摆支座(FPB) 振动台试验 减隔震 地震响应 

分 类 号：U443.22[建筑科学—桥梁与隧道工程]