单箱双室波形钢腹板PC箱梁剪力滞效应分析

摘要

Research purposes:Because of different rigidity distribution,shear-lag effects in PC box-girder with corrugated steel web are different from that in PC box-girder.In order to investigate the shear-lag effects in twin-cell PC box girder with corrugated steel web,3 D finite element model of twin-cell PC box-girder with corrugated steel web was founded by means of ANSYS,and stress distributions on typical sections were obtained.Shear-lag effects of twin-cell PC box-girder with corrugated steel web were investigated,which is compared with the ordinary PC box girder.Seven geometric parameters affecting the shear-lag effect of box girder were analyzed.Research conclusions:(1) Using corrugated steel web can enlarge the maximum shear lag coefficient of each section slightly.(2) In term of the top flange,the shear-lag coefficient of the medium web is larger than that of both sides,contrary to the bottom plate.(3) The width length ratio,the support length of the box-girder,and the thickness of the roof were confirmed as the main factor working on the shear-lag effect,and the shear lag was not influenced by the number of the diaphragms.(4) The research result are worthy of use for reference for design and analysis of PC box-girder with corrugated steel web.%研究目的:由于不同的刚度分布,波形钢腹板预应力混凝土箱梁截面剪力滞效应与普通预应力混凝土箱梁截面存在较大差异,为研究单箱双室波形钢腹板预应力混凝土箱梁的剪力滞效应,借助有限元分析软件ANSYS建立单箱双室波形钢腹板预应力混凝土箱梁空间模型,分析两种典型荷载工况下典型截面的应力分布,得到典型截面的剪力滞系数,并与普通预应力混凝土箱形梁作比较,分析讨论7种几何参数变化条件下箱梁剪力滞系数的变化情况.研究结论:(1)采用波形钢腹板略增大了各断面的最大剪力滞系数;(2)对于顶板而言,中腹板的剪力滞系数大于边腹板,底板反之;(3)剪力滞系数的主要影响参数是宽跨比、承托长度、顶板厚度,横隔板数量对剪力滞系数的影响甚小;(4)该研究成果对波形钢腹板预应力混凝土箱梁设计及计算分析具有参考借鉴价值.