Transverse Pounding Of Continuous Beam Bridge And Failure Mechanism Study Of Bridge Retainer Under Seismic Excitations

Large numbers of seismic damage shows that bridge pounding is the main reason of damage and failure of bridge structure. Based on systematically summarizing theory of bridge pounding of domestic and abroad, the paper analyzes pounding effects of transverse bridge. Influence of different parameters are studied on transvers pounding, such as pounding stiffness, gap between retainers and girders, bearing stiffness and height of piers. Referenced by ductile failure and damage theory of bridge pier, failure mechanism study of bridge retainer is performed under earthquake excitation. It induces retainer damage rates and failure characteristics of different phrase. Considering interaction of piles and slope soil, damage on substructure is analyzed under transvers pounding effect. Through changing retainer construction design, the whole bridge pounding response and influence on substructure are studied under earthquake excitations. It provides referential value to retainer construction design.The main analyses of the paper are as follows:1. Based on the brides of Baise district, a four-span continuous bridge model is built up in SAP2000. Considering of the factors of pounding stiffness, gap between retainers and girders, bearing stiffness and height of piers, the nonlinear time-history analysis is studied on bridge transvers pounding. 2. Through moment-curvature analysis of reinforcement concrete section and combining with damage and failure mechanism of bridge pier, it gets retainer damage rates and failure characteristics.3. Considering of interaction between piles and slope soil, bridge model with pile is built up and analyzed in SAP2000. The different transvers pounding response is compared between general model and bridge model with pile.4. Considering of interaction between piles and slope soil, pounding response on bridge pier and pile is analyzed, including the parameters of moment of pier and displacement and moment of top pile. Make compared analysis with substructure ultimate bearing capacity which calculated by bridge design code.5. Considering of interaction between piles and slope soil and changing construction design of retainer, the paper researches pounding response on bridge substructure of different retainer design. It mainly analyzes the factors of retainer stiffness and reinforcement and provides reference for retainer function design under earthquake.