波形钢腹板箱梁余弦剪滞函数引起的附加轴力分析

Analysis of Additional Axial Force Induced by Cosine Shear Lag Function of Box Girder with Corrugated Steel Webs

为了分析波形钢腹板箱梁在剪力滞效应计算时由于未考虑中性轴的偏移而引起的附加轴力的影响,利用受弯梁的截面不受轴力的静力平衡条件,推导出波形钢腹板箱梁在余弦剪滞翘曲位移函数下的附加轴力计算公式。引入附加轴力影响系数来衡量附加轴力的相对大小,分别针对简支梁、悬臂梁和连续梁在集中荷载和均布荷载作用下的附加轴力影响系数进行数值分析。结果表明:在两种荷载工况下,附加轴力影响系数相对较小,基本都在2%之内,对剪力滞效应的影响可忽略不计。

Based on the balance condition of the flexural beam without axial force in analyzing the effect of additional axial force of box girder with corrugated steel webs in the calculation of the shear lag effect without considering the offset caused by the neutral axis,the formulae for calculating additional axial forces of box girder with corrugated steel webs under the cosine shear lag warping displacement function are derived.For measuring the value of the additional axial force,the influence coefficient of additional axial force is introduced.The influence coefficient of additional axial force of a simple supported,a cantilever and a continuous beam are analyzed under a concentrated load and uniformly distributed loads.The results show that the influence coefficient of additional axial force is less than 2%and the effect on shear lag effect is negligible under the two load cases.