三跨斜交简支梁桥地震碰撞反应参数影响研究

Parametric Analysis of Three-Span Skewed Simply Supported Girder Bridge under Seismic Collision Response

利用OpenSees地震仿真模拟平台,建立了3×30m斜交简支梁桥计算模型,通过改变斜度、纵向伸缩缝间隙、梁体与横向挡块间初始间隙,研究结构地震碰撞反应的变化规律,研究发现:桥面峰值转角随斜度和伸缩缝间隙增大呈现先增大后减小的变化规律,随横向初始间隙增大而逐渐增大;梁体纵向最大位移随斜度和伸缩缝间隙增大而逐渐增大,随横向初始间隙增大呈现先减小后增大的变化规律;墩底最大反力和墩顶顺桥向最大位移的变化规律与梁体纵向最大位移的变化规律一致.

A dynamic calculation model of 3 × 30m skewed simply supported girder bridge is established by u- sing the software OpenSees. The variations of structure under seismic collision response is studied by chan- ging the skew angle, initial gap at expansion joint and initial gap between girder. The results indicate that the peak angle of the deck increases firstly and then decreases with the increase of the skew angle and initial gap at expansion joint, but increases with the increase of initial gap between girder~ the maximum longitudinal dis- placement of the girder increases with the increase of the skew angle and initial gap at expansion joint, but de- creases firstly and then increases with the increase of initial gap between girder; the variations of the maxi- mum reverse force and the maximum displacement of pier top along the bridge have the same variations with the longitudinal displacement of the girder.