新光大桥的动力特性和地震行波效应研究

新光大桥位于广州新光快速路主干线,是世界上第一座三跨连续钢桁拱与钢筋混凝土V型刚构结合的钢-混凝土组合体系桥梁,主桥跨度为177 428 177 m,在目前同类型桥梁中,主桥长度位居世界第一.该桥结构新颖,造型独特.文章主要针对新光大桥的动力特性和地震行波效应进行了详细研究.在两水准、两阶段抗震设防思想下给出了主要控制构件在考虑行波效应情况下的内力,并与纵桥向地震一致激励作用下的内力进行了比较;同时给出了在不同剪切波速下,主拱顶截面的位移时程曲线.研究表明行波效应以及地面剪切波速度对大跨度连续刚架钢桁拱桥的地震响应有着较大的影响.

Study on dynamic properties and traveling wave effect of Xinguang Bridge

Xinguang Bridge locates at Xinguang Express Way of Guangzhou City.It is the first 3-span continuous rigid-frame and steel-truss arch bridge with reinforced concrete V-shaped rigid frame in the world.The span of the main bridge is 177 428 177 m.Among the same type of the bridges,the length of the main bridge is largest in the world.The style of the bridge is unique and fashionable.This paper is focused on the study on the dynamic properties and traveling wave effect of Xinguang Bridge.Under the condition of two steps and two levels probability the seismic responses considering traveling wave effect are analyzed in detail.Comparing with the internal forces subjected to coincident earthquake excitation,furthermore providing the displacement time history curve of main arch crown of the bridge at different shear wave speed of ground,it is found that traveling wave effect and shear wave speed of ground has great influence to the seismic response of large span continuous rigid-framed and steel-truss arch bridge.