Effectiveness of Rubber Cushion to Mitigate Pounding between Girders and Blocks of Curved Bridge Subjected to Strong Ground Motion

摘要

A series of nonlinear dynamic analysis is conducted for a bridge system consisting of two eight-span curved bridges with total length of 378.92 m supported by isolation bearings subjected to strong earthquake ground motions. Acceleration and relative displacement response of two decks, the initial gap, and the rubber cushion hardness are analyzed. This study describes a numerical analysis to clarify the effectiveness of rubber cushion to mitigate pounding effect between girders and blocks. The pounding effect is idealized by the impact spring. The study indicate that the application of rubber cushion makes the rotation center of curved bridge transfer and the offset direction change. The reasonable selection of parameters of initial gap and hardness have great influence on the pounding of girders and blocks. In present study, the hardness of Shore A 55 is appropriate.