脉冲型近场地震下HDR隔震简支梁桥参数研究  

Study on parameters of seismic isolated simple-supported beam bridges with HDR under pulse-type near-field earthquake

作　　者：李宇[1] 陈明 赵国辉[1] LI Yu;CHEN Ming;ZHAO Guohui(School of Highway,Chang'an University,Xi'an Shaanxi 710064,China)

机构地区：[1]长安大学公路学院,陕西西安710064

出　　处：《中国安全科学学报》2020年第10期141-148,共8页China Safety Science Journal

基　　金：国家自然科学基金资助(51408042);长安大学中央高校基本科研业务费专项资金资助(300102219212);云南省交通运输厅科技项目(云交科教[2018]13号)。

摘　　要：为研究脉冲型近场地震动作用下简支梁桥设计参数对其隔震后地震响应的影响,采用结构分析软件SAP2000建立设置高阻尼橡胶(HDR)支座的隔震简支梁桥等效单墩模型,以典型近场地震动作为输入,得出桥墩高度、桥墩质量和等效隔震度对HDR隔震简支梁桥的近场地震动响应的变化曲线。研究结果表明:桥墩越矮,HDR隔震简支梁桥的等效周期增幅就越大;桥墩越高,HDR隔震简支梁桥的梁体位移峰值也就越大;当墩高大于35 m,HDR隔震效果不明显;桥墩质量的增大对HDR隔震效果不利;HDR隔震简支梁桥的近场地震动响应与等效隔震度有很强相关性,即当等效隔震度小于2.0时,HDR隔震效果较差;而当等效隔震度大于3.0时,HDR隔震效果则随等效隔震度增加而增强。In order to study impacts of design parameters of simple-supported beam bridges on seismic response under pulse-type near-field earthquake motion,equivalent single-pier model of seismic isolated simple-supported beam bridges with HDR bearing were built by using SAP2000.Then,with typical nearfield earthquake motions as inputs,change curves of seismic response of HDR beam bridges influenced by pier height and mass and equivalent isolated degree were obtained.The results show that the shorter the pier is,the larger equivalent period of beam bridges will increase.The higher it is,the greater peak displacement is.Meanwhile,seismic isolation effect of HDR is reduced when pier is more than 35 m high.Increase of pier mass has a adverse effect on it.Moreover,equivalent isolated degree of HDR has strong correlation with near-field seismic response of these beam bridges.When it is<2.0,seismic isolation effect will be bad but will improve along with increase of equivalent isolated degree when it is>3.0.

关 键 词：近场地震动 高阻尼橡胶(HDR)支座 隔震简支梁桥 等效单墩模型 等效隔震度 

分 类 号：X915.5[环境科学与工程—安全科学] U448.27[建筑科学—桥梁与隧道工程]