Seismic Response Analysis Of Urban Curved Bridge

Along with the rapid development of city construction, various interchange constantly is emerging, curved bridge for its line arranged flexibly, beautifulstyles and shapes and is widely used in city interchange project. As theimportant urban lifeline project,the curve bridge’s seismic research to ensure that lifeline open after the quake, reduce the occurrence of secondary disasters earthquake has very important significance.Taking the Lanshan Road Donggang interchange ramp D Bridges in Lazhou for engineering background, and the dynamic, curve bridge spectrum and nonlinear time history are analysed, the thesis research content as follows:(1) The development situation of curved bridge and earthquake characteristics are introduced briefly, the present situation of seismic research of curved bridge is summarized.(2) Basing on the engineering background, different finite element analysis models only changed curvature radius are created. The influence of dynamic characteristics, structure spectrum analysis mode selection, the number two piers bending spindle direction of internal force of the coupling effect and the earthquake response caused by the radius of curvature’s change are discussed.(3) Using the0°～180°rotating stimulation method, response spectrum of one-way incentive of this models are analysed, the influence of earthquake response for curved bridge caused by the motion input direction, the rule between the most unfavorable input direction and earthquake response and the radius of curvature is analysed, the incentive method provided by Code for seismic design of urban bridges is compared, and the effectiveness of0°～180°rotating incentive method is proved for small radius city curve ramp Bridges.(4) The response spectrum one-way incentive is analysed by using the same incentive method of linear bridge, the most internal force gotten by this method is compared with the0°～180°rotating incentive method. The necessity of ensuring the most unfavorable input direction is stated when the earthquake response is been analyzing for curved bridge.(5) Basing on the0°～180°rotating incentive method’s application in earthquake response of the yield surface function and allowing only a single response in the determination of the most unfavorable incentive on the direction is discussed.(6) According to the engineering background, plastic hinge unit model and elastic-plastic fiber element model are created, the influence of curve bridge nonlinear seismic response of this2models is studied by Nonlinear time history response analysis.