多点非一致激励下高墩连续刚构桥的地震响应  

Seismic response of a continuous rigid frame bridge with high piers to multi-support asynchronous excitations

作　　者：贾宏宇[1] 康锐[1] 夏明强 郑史雄[3] 

机构地区：[1]西南交通大学土木工程系,四川峨眉614202 [2]青藏铁路公司,青海西宁810000 [3]西南交通大学土木工程学院,四川成都610031

出　　处：《福州大学学报（自然科学版）》2013年第4期523-527,共5页Journal of Fuzhou University(Natural Science Edition)

基　　金：铁道部科技研究开发计划资助项目(2010-G018-A-4)

摘　　要：为研究多点非一致激励对高墩连续刚构桥地震响应的影响规律,以某跨径为48 m+96 m+48 m的组合高墩连续刚构桥为算例,建立高墩连续刚构桥的三维有限元数值模型,计算高墩连续刚构桥在纵向随机地震动激励下,考虑视变化的波速以及视波速随地震动频率变化时的多点激励响应分析.研究结果表明:主梁的纵向位移、横向弯矩和轴力响应及桥墩的纵向位移、横向弯矩和纵向剪力响应随着视波速的变化有所不同,与常数视波速100 m.s-1下结构的响应相比,视波速随频率变化情况下的响应量显著增大,1号墩处主梁的纵向位移、横向弯矩和轴力分别增大了2.03、1.39和1.37倍,1号墩、2号墩墩顶的纵向位移、墩底横向弯矩和墩底的纵向剪力均增大约1.37倍.考虑随频率变化的视波速对高墩连续刚构桥的影响是必要的.To investigate response rule of a continuous rigid frame bridges with high piers subjected to multi-point stochastic seismic excitations including mainly traveling wave effect,taking a realistic continuous rigid frame bridges with high piers with the layout of 48 m＋96 m＋48 m for example and building 3D FE model,many of studies are conducted that different apparent wave velocities without changing and these with changing in different frequencies have significant effects on response of HPCRFB under longitudinal random seismic excitations.Many conclusions are drawn that longitudinal displacements and transverse moments,and axial forces of main beam,longitudinal displacements and transverse moments,and shear forces of the piers will vary due to different apparent velocities of earthquake,compared to structure responses under apparent velocity 100 m·s-1,longitudinal displacements,and transverse moments,and axial forces at No.1 pier of main beam are 2.03、 1.39 and 1.37 times before,respectively,longitudinal displacements on pier top,transversal moments and longitudinal shear forces at the bottom of No.1 pier and No.2 pier increase about 1.37 times before,it is of prime necessity to consider traveling wave effect of the wave velocity changing due to different frequency in seismic analysis of the continuous rigid frame bridges with high piers.

关 键 词：刚构桥 高墩 地震响应 非一致激励 

分 类 号：TU311.3[建筑科学—结构工程]