可液化河谷场地简支梁桥的地震反应分析  

Seismic Demand Analysis of a Simply Supported Girder Bridge in Liquefied or Non-liquefied Ground

作　　者：王晓伟[1] 李闯[1] 叶爱君[1] 商宇[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《中国公路学报》2016年第4期85-95,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51278375)

摘　　要：为分析可液化河谷场地简支梁的地震反应,首先基于OpenSees,采用二维场地-结构整体化模拟方法对某离心机试验进行了数值模拟,并验证模拟方法的可靠性;然后建立了一座典型河谷场地-三跨简支梁桥的有限元模型,分析场地液化与否对场地及简支梁桥各部件地震反应的影响。结果表明:与输入地震的加速度谱相比,液化场地可延长地表土体加速度反应的卓越周期;与场地未液化相比,场地液化可导致地面大变形,桩基础在桩顶和土层分界处的弯矩、桥墩倾斜程度、滑动支座位移均有所增加,但场地液化与否对墩底弯矩的影响很小。In order to analyze seismic response of a simply supported bridge in liquefiable river valley,numerical simulation of a centrifuge testing was conducted based on OpenSees by the two dimensional site-structure integration simulation method to verify the reliability of the simulation method.A finite element model of typical simply supported three-span bridge in river valley was then established.And the effects of ground liquefaction on the seismic response of the site and all parts of the simply supported bridge were analyzed.The results show that,compared with the acceleration spectrum of input ground motion,ground liquefaction extends the predominant period of the acceleration response spectrum in the valley surface.Besides,compared with nonliquefied ground,ground liquefaction remarkably increases the deformation in the ground surface,bending moment of piles foundation in pile top and soil division section,the inclination of piers and the displacement of sliding supports.However,the effect of ground liquefaction on bending moment at pier bottom is little.

关 键 词：桥梁工程 地震反应 有限元方法 简支梁桥 液化 

分 类 号：U447[建筑科学—桥梁与隧道工程]