Seismic Analysis Of Three-Span Cantilever Beam Viaduct With Pounding Effects And Restrainers

China is one of the countries with lots of earthquake happen in the world. Following the acceleration of the city modernization, the increase of the urban population and the development of the economic, the urban disaster prevention and mitigation have been gained more and more attentions. Transportation system is the most important components of the urban lifeline system, and whether the safety of the bridge structure, including freeway, railroad viaduct, crossroads and city artery viaduct, is key content to assure the effective post-earthquake rescue.Most of post-earthquake survey revealed that the pounding damage and unseating of the bridge girders are the two main forms of bridge damage. Setting base-isolation system and restrainers could be used to reduce the structural response and prevent the unseating of the bridges. Aiming at the pounding and unseating problem, this paper analyzed the structural response selecting a three-span cantilever beam bridge as the object. The main contents include;1. Seismic responses analysis of a three-span cantilever beam bridge including the pounding effects. Using the ANSYS finite element analysis software package, the finite element analysis model of the bridge was established considering the lead rubber bearings, potential nonlinear plastic joint of pier at the bottom, P ?? effect and nonlinear restrained device.2. Analyzing the difference of the structural responses of bridge with and without pounding effects and the effects of the earthquake spectrum characteristics. The analysis results indicated that pounding induce strongly increase the acceleration and the relative displacement between the adjacent bridge segments. Pounding also increase the possibility of the bridge unseating.3. Analyzing the effect of the restrainers on the pounding and unseating of the bridge structures and the optimal stiffness of the restrainers. The analysis results showed that the restrainer can effectively control the relative displacement between two spans and prevent bridge unseating.