中等跨度斜拉桥抗震结构体系研究

A Research of Seismic Structure System of Medium-span Cable-stayed Bridge

为研究中等跨度斜拉桥抗震结构体系,以南京秦淮新河大桥为工程背景,采用非线性时程法分析不同抗震体系情况下结构的地震响应。研究表明:塔、梁之间设置粘滞阻尼器不仅可以控制关键位置的位移,而且可以明显降低塔底的地震内力;过渡墩上横向固定支座剪坏滑动不仅可以避免对横向固定支座的抗剪能力提出过高要求,而且大大降低了过渡墩的地震内力响应。

With the engineering background of Nanjing Qinhuai New River Bridge, nonlinear time history analysis is selected to obtain seismic responses of bridges with different seismic systems in order to study the seismic system of cable-stayed bridge with medium-span. It is found that the viscous fluid dampers are equipped between bridge tower and beam, which not only efficiently diminishes the displacement of girder, but also obviously decreases the seismic force of tower bottom. When the transverse-fixed bearings on the side piers are sliding during the earthquake, shear capacity of bearings can be largely reduced and seismic force of the side piers can be greatly decreased.