某半飘浮体系独塔斜拉桥抗震性能研究  

Study on Aseismic Behavior of Semi-Floating System Single Pylon Cable-Stayed Bridge

作　　者：郭红雨 GUO Hongyu(JSTI Group Co.,Ltd.,Nanjing 210019,China)

机构地区：[1]苏交科集团股份有限公司,南京210019

出　　处：《现代交通技术》2020年第2期52-56,73,共6页Modern Transportation Technology

摘　　要：为研究半飘浮体系下独塔斜拉桥的抗震性能,以某全长415 m的两跨组合梁斜拉桥为例,采用大型有限元分析软件Midas Civil,建立动力有限元模型,分别对其进行自振特性、反应谱和非线性时程分析,并评价其抗震性能。结果表明:仅设置竖向支撑的飘浮体系独塔斜拉桥一阶振型为塔梁纵飘,应在其纵桥向设置粘滞阻尼器以限制主梁位移;横桥向设置抗风支座的传统硬抗体系已经难以适应较大的地震烈度,必须采取有效的减隔震方案,以适当降低控制截面的地震响应。根据案例桥梁的结构特点,综合考虑各控制截面的地震响应,选取合适的阻尼参数,在桥塔和主梁间布置横向独立钢阻尼装置,并在过渡墩和主梁间布置弹塑性钢阻尼支座,该布置方式对大桥的减震效果最佳,证明此减隔震设计方案合理可靠。Under the background of steel and concrete composite girder cable-stayed bridge with the length of 415 m,the aseismic behavior of semi-floating system single pylon cable-stayed bridge was studied.A dynamical finite element model was established,using the software Midas Civil,the study on dynamic characteristics,response spectrum and the nonlinear timehistory analysis of this bridge were respectively made,and the aseismic behavior of this bridge was also evaluated.The results show that the first vibration mode of single pylon cable-stayed bridge with only vertical bearings was girder and pylon floating,the longitudinal fluid viscous dampers should be arranged reasonably to reduce displacement at the end of girder;the lateral fixed system with wind-resistant supports resist the earthquake difficulty,the lateral seismic mitigation and isolation schemes should be used to reduce seismic responses of key sections properly.According to the structural characteristics of this bridge,under the optimal parameters,between the pylon and main girder,the lateral steel damper was arranged separately,and between the side piers and main girder,the elastic-plastic steel damper bearings were arranged,the seismic mitigation effect of this distributing dampers is prominent when all seismic responses of key sections were considered,the seismic mitigation and isolation design of this bridge was reasonable.

关 键 词：桥梁工程 独塔斜拉桥 地震响应 动力特性 减震设计 粘滞流体阻尼器 钢阻尼器 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]