旋转地震合成及其在大跨度悬索桥中的应用  

Rotational seismic synthesis and it’s application in long span suspension bridges

作　　者：蓝先林 马白虎 贾宏宇[3] 徐向东 杜镔[1] LAN Xianlin;MA Baihu;JIA Hongyu;XU Xiangdong;DU Bin(Guizhou Transportation Planning Survey and Design Academe Co.Ltd.,Guiyang 550081,China;Highway Administration Bureau of Guizhou Province,Guiyang 550081,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]贵州省交通规划勘察设计研究院股份有限公司,贵州贵阳550081 [2]贵州省公路开发有限公司,贵州贵阳550081 [3]西南交通大学土木工程学院,四川成都610000

出　　处：《世界地震工程》2023年第1期164-172,共9页World Earthquake Engineering

基　　金：国家自然基金面上项目(52178169);贵州省重大科技专项计划项目(黔科合重大专项字[2016]3013);贵州省交通运输厅科技项目2020-123-023。

摘　　要：为探究旋转地震动在大跨度悬索桥中的应用,首先,从线弹性理论和功率谱角度基于随机振动理论提出了6维地震动加速度功率谱模型;其次,基于MATLAB编制旋转地震动人工地震合成程序,从反应谱角度对合成地震动进行了正确性验证和拟合精度迭代调整;最后,分析了旋转地震动与地震动入射角对桥梁结构地震响应的影响。研究表明:人工合成的地震动平动分量反应谱与实测地震动的平动分量反应谱吻合度较高;六维地震动的主梁跨中竖向位移越是三维平动地震动的3倍,而主缆轴力峰值接近2.25E+05kN,约是三维平动地震动的1.3倍;旋转地震动和地震动入射角将会加大桥梁结构的位移响应和内力响应,且会减小塔底截面和桩最不利截面的安全性。In order to explore the application of rotational ground motion in long-span suspension bridge,a 6-D power spectrum model of ground motion acceleration based on random vibration theory is proposed from the perspective of linear elasticity theory and power spectrum.Secondly,the artificial earthquake synthesis program of rotational ground motion is compiled based on MATLAB.The correctness of synthetic ground motion is verified and the fitting accuracy is adjusted iteratively from the perspective of response spectrum.Finally,the influence of rotational ground motion and incident angle of ground motion on seismic response of bridge structure is analyzed.The results show that the synthetic response spectrum of translational component of ground motion is in good agreement with the measured response spectrum of translational component of ground motion;the vertical displacement of main girder in span of six dimensional ground motion is three times of that of three-dimensional translational ground motion,and the peak axial force of main cable is close to 2.25E+05kN,which is about 1.3 times of that of 3D translational ground motion.Rotation ground motion and incident angle of ground motion will increase displacement response and internal force of bridge structure.The safety of the bottom section and the pile section will be reduced.

关 键 词：旋转地震动 地震动合成 大跨度悬索桥 地震响应 

分 类 号：TU311.3[建筑科学—结构工程]