不同支承方式下三跨波形钢腹板连续梁弯桥剪力滞效应分析

Analysis on Shear Lag Effect of Continuous Beam Curved Bridge with Three-span Corrugated Steel Webs under Different Supporting Modes

为研究不同的支承方式对三跨波形钢腹板连续梁弯桥剪力滞效应的影响,采用大型通用有限元分析软件ANSYS建立了三跨波形钢腹板连续梁弯桥的三维有限元模型,考虑了2种典型荷载工况——跨中集中荷载和全桥分布荷载下,典型截面的应力分布情况,计算出截面的剪力滞系数,并对4种不同支承方式下的剪力滞效应进行了分析。研究结果表明,三跨波形钢腹板连续梁弯桥边跨跨中截面应力最小为固定支承,中间支座截面应力最小为中间偏心铰支承,中跨跨中截面应力最小为固定支承。内侧的剪力滞系数要大于外侧,集中荷载下的剪力滞系数要大于均布荷载下的剪力滞系数,各支承方式下的剪力滞系数差异不大,集中荷载作用下剪力滞系数最小的为中间偏心铰支承,分布荷载作用下剪力滞系数最小的为中间固定墩支承。

In order to study the influence of different supporting modes on the shear lag effect of continuous beam curved bridge with three-span corrugated steel webs,a three-dimensional finite element model of a continuous beam curved bridge with three-span corrugated steel webs is established by using ANSYS.Considering the stress distribution of typical sections under two typical load conditions-concentrated load in the middle span and distributed load in the whole bridge,the shear lag coefficients of the sections are calculated and the shear lag effects under four different supporting modes are analyzed.The results show that the minimum cross section stress of middle span is fixed support,the minimum cross section stress of middle support is middle eccentric hinged support,and the minimum cross section stress of middle span is fixed support.The hysteresis coefficient of the inner side is greater than that of the outer side,and the hysteresis coefficient of the concentrated load is greater than that of the uniformly distributed load.There is minor difference in the shear lag coefficient between different supporting modes.The one with the smallest shear lag coefficient under concentrated load is the middle eccentric hinged bearing,while the one with the smallest under distributed load is the middle fixed pier bearing.