相邻梁段周期比对伸缩缝处的碰撞响应分析

Analysis on Pounding Response of Period Ratio between Two Adjacent Continues Girders on Expansion Joint

针对相邻两联连续梁桥伸缩缝处的碰撞现象,基于其周期不一致而表现出的动力差异性,进行动力时程分析,采用直接积分法研究了地震作用下相邻联的非同向振动和伸缩缝处的碰撞响应。分析结果表明:不同周期比的相邻梁体,在地震动作用下产生的碰撞响应不同,加速度峰值小持续时间长的地震波对伸缩缝处的碰撞响应较小;碰撞对严重不同向振动的相邻两联(T2/T1<0.5)的地震响应影响很大,随着相邻两联周期比的增大,碰撞对结构地震反应影响逐渐减小。

According to the pounding phenomena of expansion joints betw een tw o adjacent continues girders,we analyzed the dynamic time history basing on dynamic differences appeared from the inconsistent period. The out- of- phase vibration and pounding response of expansion joints were also investigated under the longitudinal earthquake by direct numerical integration method. The analysis results show that the pounding responses of the adjacent girder in different period ratios were different under earthquake. The pounding responses of the earthquake with small acceleration peak value and long duration on the expansion joints were small. The pounding had a remarkable influence on seismic response of tw o adjacent girders（ T2/ T1〈 0. 5） of out- of- phase vibration. With the increase of the period ration betw een tw o adjacent girders,the seismic response of structure decreased under pounding effect.