摘要
为研究大跨度连续梁拱组合桥梁的地震响应规律,以兰渝线上某(82+172+82)m连续梁拱组合桥为例,建立考虑桩土共同作用的有限元分析模型。分别采用反应谱和时程分析法研究该桥的地震响应特点,探讨高阶振型、几何非线性、竖向地震作用及行波效应等因素对桥梁地震响应的影响。分析结果表明:该桥内力最大出现在拱脚处;截面内力主要由低阶振型(前30阶)控制,高阶振型的贡献较小;几何非线性对该大桥的地震响应影响较小,内力最大仅增加2.21%;竖向地震作用对截面轴力和面内弯矩起控制作用,其放大倍数最大可达2.88倍;行波效应对大跨度梁拱组合桥地震响应的影响不可忽视。
For analyzing the seismic response rule of long -span continuous arch -beam bridge,taking a （82 ＋172 ＋82）m long -span continuous beam -arch bridge on the Lanzhou -Chongqing railway as an example,the finite element model considering the interaction between pile and soil was established.The seismic response of the bridge was analyzed by the method of response spectrum and time -history analysis.It was discussed that the higher modal shape,geometrical non -linearity,vertical seismic action,traveling wave effect and so on had im-pact on the seismic response.The analysis results show that the largest internal force happens on the arch feet;The sectional internal force mostly depends on lower modal shapes（the first 30 modal shapes）,while the contri-bution of higher modal shapes is small;Geometrical non -linearity has little effect on the internal force of the bridge,and the largest increase of internal force is only 2.21%;The vertical seismic action has a remarkable im-pact on the internal force of axial force and moment,whose largest magnification can reach 2.88 times;When analyzing the seismic response of long -span continuous beam -arch bridge,the traveling wave effect should be considered.
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2015年第3期557-563,共7页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(51378503)
高速铁路基础研究联合基金资助项目(U1334203)
中国博士后科学基金资助项目(2014M552158)
关键词
梁拱组合桥
地震响应
高阶振型
竖向地震作用
行波效应
beam -arch bridge
seismic response
higher modal shape
vertical seismic action
traveling wave effect
