板式橡胶支座桥梁纵桥向墩梁相对位移碰撞效应分析

Analysis of pounding on longitudinal relative displacement between pier and girder of bridges on laminated rubber bearing

针对典型的板式橡胶支座连续梁桥,考虑强震作用下板式橡胶支座的滑动效应、工程场地类别及地震动特性的影响,研究了相邻桥联间的碰撞效应对纵桥向墩梁相对位移峰值的影响规律。结果表明:随着相邻联周期比的增加,伸缩缝处碰撞次数与最大碰撞力均逐渐减小;墩梁相对位移峰值受地震波特性影响较大,相邻联之间的碰撞未必加剧落梁危险性;长周期联墩梁相对位移峰值受碰撞效应影响较短周期联大。

For the typical continuous girder bridges supported on laminated rubber bearings, the variation of pounding between adjacent girders on the peak relative displacements between the top of pier and girder was analyzed considering the sliding response of laminated rubber bearings under earthquake, site classifications and characteristics of earthquake.The results showed that the number of poundings and the maximum impact force of expansion joints decreased with the increase of the period ratio of adjacent bridges. Meanwhile, the peak relative displacements between the top of pier and the girder were determined by characteristics of earthquake.The pounding between adjacent bridges could not exacerbate the risk of falling girder. Furthermore, the peak relative displacements between the top of pier and the girder of long period bridges were affected by pounding greater than short period bridges.