带剪切连梁双柱式桥墩地震响应特性振动台试验研究  

SHAKING TABLE TESTS ON THE SEISMIC RESPONSE CHARACTERISTICS OF DOUBLE-COLUMN PIERS WITH SHEAR BEAMS

作　　者：谢文[1] 何天涛 孙利民[3] XIE Wen;HE Tian-tao;SUN Li-min(School of Civil and Environmental Engineering,Ningbo University,Ningbo 315211,China;Ningbo Municipal Facilities Center,Ningbo 315010,China;State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]宁波大学土木与环境工程学院,宁波315211 [2]宁波市市政设施中心,宁波315010 [3]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《工程力学》2021年第5期171-181,共11页Engineering Mechanics

基　　金：国家自然科学基金项目(51608282,91315301-05);浙江省自然科学基金项目(LY20E080010)。

摘　　要：为了研究剪切连梁对双柱式桥墩地震响应的影响,该文将双柱式桥墩和带剪切连梁双柱式桥墩置于全桥模型中开展振动台试验研究,其中带剪切连梁双柱式桥墩沿墩等间距附有5根剪切连梁。因此设计了一座几何相似比为1/70且包含桥墩(含双柱式桥墩和带剪切连梁双柱式桥墩)、主塔、主梁、群桩和模型土等在内的斜拉桥试验模型并开展振动台试验,比较研究人工波、El Centro波和Mexico City波等不同频谱特性地震作用下双柱式桥墩和带剪切连梁双柱式桥墩的地震响应特性。试验结果表明:与双柱式桥墩结果相比,在人工波、El Centro波和Mexico City波作用下,带剪切连梁双柱式桥墩的墩底最大应变明显减小,表明附加的剪切连梁可有效降低墩柱的弯矩应变响应,实现了剪切连梁起分散墩柱受力的作用;与振动台输出最大加速度相比,三条地震波作用下带剪切连梁双柱式桥墩的墩底加速度放大1.4倍~1.8倍,表明桩-土-结构相互作用对纵向加速度产生不利影响,具有明显放大效应;地震输入的频谱特性明显影响双柱式桥墩和带剪切连梁双柱式桥墩的加速度、位移和应变等地震响应,且其影响程度取决于地震输入卓越频谱与结构频率特性之间的相关关系。Shaking table tests were carried out to study the influences of shear beams on the seismic response of double-column piers that were designed to support the girder of a full cable-stayed bridge model.The doublecolumn pier with shear beams included two columns and five shear beams equally installed between the two columns.A full cable-stayed bridge model of 1/70-scale that included the pier(a double-column pier and a double-column pier with shear beams),tower,girder,pile group,and artificial soil was designed and tested on a shaking table array.The seismic response characteristics were compared between the double-column piers with and without shear beams when they were subjected to various earthquake waves of various frequency contents,such as the artificial,El Centro,and Mexico City waves.The experimental results show that the maximum strains at the bottom of the double-column pier with shear beams were less than those of the double-column pier under the artificial,El Centro wave,and Mexico City waves of various shaking amplitudes.The additional shear beams significantly mitigated the strain responses at the bottom of the double-column pier,and decentralized the inner force of the columns.The maximum accelerations at the bottom of the double-column pier with shear beams are1.4-1.8 times those of the shaking table when the bridge model was subjected to the artificial,El Centro,and Mexico City waves with 0.1 g,0.15 g,and 0.2 g.The pile-soil-structure interaction significantly affected the seismic response of the double-column pier with shear beams and increased its longitudinal acceleration responses.The seismic responses,such as the acceleration,displacement,and strain responses of the doublecolumn pier with and without shear beams were significantly affected by the frequency spectral characteristics of the various earthquake waves.The extent of the influence was dependent on the relationship between the frequency contents of the earthquake waves and the frequency spectral characteristics of the piers.

关 键 词：剪切连梁 振动台试验 双柱式桥墩 桩-土-结构相互作用 频谱特性 

分 类 号：U448.34[建筑科学—桥梁与隧道工程]