设柔性中央扣的特大跨度悬索桥纵向抗震体系研究  

Longitudinal Anti-Seismic System for Long-Span SuspensionBridge with Flexible Central Buckle

作　　者：郭志明 汪鸿鑫 叶爱君[2] GUO Zhi-ming;WANG Hong-xin;YE Ai-jun(Nanjing Public Project Construction Center, Nanjing 210019, China;State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China)

机构地区：[1]南京市公共工程建设中心,江苏南京210019 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《桥梁建设》2020年第1期38-43,共6页Bridge Construction

摘　　要：为针对设有柔性中央扣的特大跨度悬索桥选择合理的纵向抗震体系,以设有柔性中央扣的南京仙新路特大跨度悬索桥(主跨1760 m的双塔单跨地锚式悬索桥)为背景进行研究。采用SAP 2000软件,考虑柔性中央扣只能受拉不能受压的力学特性建立该桥非线性有限元模型,对柔性中央扣、粘滞阻尼器以及两者组合作用的减震效果进行对比分析,在此基础上提出合理的减震体系,并确定合理的体系参数。结果表明:粘滞阻尼器的减震效果远好于柔性中央扣;在设有柔性中央扣的特大跨度悬索桥中,由于柔性中央扣在地震作用下会被拉断而失效,因此建议将柔性中央扣的销钉设计为“熔断”部件,同时在塔、梁连接处设置粘滞阻尼器减小加劲梁地震位移;粘滞阻尼器的参数应综合考虑静力和地震响应优化确定。To select a rational longitudinal anti-seismic system for the long-span suspension bridge with flexible central buckle,the long-span suspension bridge on the Xianxin Road in Nanjing,which is a two-tower single span earth-anchored suspension bridge with a main span of 1760 m,was taken as the study background.The software SAP 2000 was used to build the nonlinear finite element model of the bridge,taking into consideration of the mechanical property of the flexible central buckle that can bear tensile forces and cannot accommodate compressive force.The seismic mitigation effects of the flexile central buckle and viscous dampers as well as the collaborated effect of the two were compared and analyzed,based on which,a rational anti-seismic system was proposed and the rational systematic parameters were determined.The results show that the seismic mitigation effect of viscous dampers is far better than that of the flexible central buckle.In the long-span suspension bridge,the flexible central buckle is possible to be pulled to break,and thus fail under the action of earthquakes,therefore,it is suggested that the pins be able to function like circuit breakers,and viscous dampers be installed at the tower-girder connections to reduce the displacement of the stiffening girder induced by earthquakes.When determining the parameters of the viscous dampers,the static forces and seismic responses should be considered.

关 键 词：悬索桥 柔性中央扣 粘滞阻尼器 纵向抗震体系 减震效果 参数优化 有限元法 

分 类 号：U442.25[建筑科学—桥梁与隧道工程] U442.55[交通运输工程—道路与铁道工程]