Seismic Displacements Reduction for a Long-Span Cable-Stayed Bridge
Floating or semi-floating systems are usually employed for long-span cable-stayed bridges to lengthen their fundamental periods, and accordingly, to reduce their seismic inertial force, but the structures’ seismic displacements could be increased by utilizing these systems. Taking Yong-jiang railway cable-stayed bridge which has a low center of gravity as engineering background, the function of viscous dampers in controlling seismic displacements is studied. Firstly, the rational parameters of dampers are determined by parametric analysis, and then the seismic displacements and forces of the bridge, utilizing and un-utilizing viscous dampers, are compared. The results show that: viscous dampers are efficient in controlling seismic displacements of the bridge; the seismic shear forces at the bottom of towers are reduced slightly and the corresponding moments are reduced in a larger extent for cable-stayed bridge with low center of gravity.