Research Of Anti-Seismic Measures For Long Span Single Tower Cable-Stayed Bridge

It is well known, in general, that the long-span bridge is the hinge of transportation, which is heavily invested in, used frequently and has important influence on national economy. Once destroyed, it will lead to huge economic lose and heavily influence earthquake disaster reduction and repair of disaster area. So it is very important to adopt the effective seismic fortification measures to insure the safety of the structure under earthquake.When we take the earthquake-reduction design of cable-stayed bridge into account, the small internal force and the displacement are anticipated to get under the seismic shock, traditionally, if a cable-stayed bridge was designed without any aseismatic measures, small internal force always according with great displacement. In this thesis, three finite element models for a single tower cable-stayed bridge by MIDAS/CIVIL are established, which are without earthquake-reduction measure, with cable retainer and with viscous damper. Then, through modal analysis and time-history analysis, the effect of cable retainer and viscous damper are studied. It is showed that the viscous damper could lower the displacement and internal force reaction at the same time. So it can increase the aseismatic ability and the durability of the cable-stayed bridge, and can accord with the idea of the aseismatic design.These laws can be used as the basis of aseismatic design of the bridge and is useful for directing aseismatic analysis and earthquake-reduction design of such kind bridge.