某桥梁段剪力滞效应研究与分析

Analysis and Research of a Bridge Section Shear System Effect

本文以赤山大桥工程为背景,研究在施工阶段重力及预应力作用下混凝土结构的剪力滞效应,通过有限元模拟悬臂施工全过程的方法,随着后浇注节段数量增加剪力滞系数呈现递减规律。表明箱梁节段剪力滞效应一般都是在其刚浇注时最大,未施加横向预应力以及预应力钢束起弯角度越小,则说明宽高比,宽跨比越大,剪力滞效应也很明显。并且通过对该桥施工监控,把计算值与实测值进行了对比,而腹板厚度和M锚固位置的变化则对该效应影响不甚明显,对有限元结果进行了验证,验证了计算分析的合理性。对实践工作具有一定的指导意义,希望能更多地运用于实践当中。

Abstract： In this paper, making Chishan bridge projeet as the beckground, through finite element simulation of the whole process of cantilever construction method, research in the eonstrutction stage of gravity and prestressed concrete structure subjected to shear lag effect, showed segmental box girder shear lag effect is generally maximum in the just pouring,after pouring secting increases the amount of shear lag coefficient shows law of diminishing. Aspect ratio,width to span ration is larger,without lateral preastress of prestressed steel beam and the bending angle is small, the shear lag effect is obvious. And web thickness and M anchoning positong changes the effect is not SO obvious. And through to the bridge construction monitoring, comparing the calculated values and the measured values,and result of calculation is compared correct.