Seismic Performance Assessment of Long Span Continuous Rigid Bridge

Abstract

Based on the theory of cantilever construction, combined with a three cross continuous rigid frame bridge, choosing the biggest cantilever stage, side span cross fold stages, middle span cross fold stage and complete bridge stage as the research object. Considering the pillar-soil function, making the seismic elastic-plastic response calculation. Getting the result that, during the earthquake, pillar-soil function can improve the flexible extension ability of the bridge structure so as to get better resistance seismic capacity. Internal force of the construction stage gradually reduces along the bottom pier, the middle pier and the top pier. Along the bridge, the maximum bending moment appears at the biggest cantilever stage. Horizontal to the bridge, the maximum bending moment appears at the side span cross fold stages. Plastic areas develops quickly during pier bottom and pile top, the crack is obvious; Plastic hinge first appears in the pile foundation, consuming earthquake energy through its plastic deformation so as to reduce the earthquake impact of pier. We should try to avoid plasticitys appearing in the pile foundation during the design, which will provide convenience for the follow-up maintenance.