波形钢腹板组合箱梁剪力滞效应的理论与试验研究

Theoretical and Experimental Study on Shear Lag Effect of Composite Box Girder with Corrugated Steel Webs

基于能量变分法原理推导了波形钢腹板组合箱梁在集中荷载和均布荷载作用下的剪力滞效应计算公式,讨论了波高区混凝土的合理计算宽度取值问题;制作了2根模型梁、并进行了在集中荷载和均布荷载作用下的加载试验,通过实测箱梁翼板的纵向应力分布来研究这种组合结构在外荷载作用下的剪力滞效应的变化规律;在此基础上利用空间有限元分析程序进行了数值分析。结果表明:剪力滞系数的理论值、模型实测值以及空间有限元计算值吻合良好,波高区混凝土按1倍波高进行取值计算时结果偏于安全;集中荷载相对于均布荷载而言,其剪力滞系数较大;结果证明了本文公式可用于波形钢腹板组合箱梁的剪力滞效应计算。

In order to study the shear lag effect of the composite box girder with corrugated steel webs under concentrated load and uniform load,the calculation formulas were deduced by the energy-variatinal method,and the reasonable width of concrete of corrugated height was discussed.Two model tests under concentrated load and uniform load were performed,and the disciplinarian of the shear lag effect under loads was analyzed based on the measured longitudinal stresses on flange plate of concrete box girder.Spatial analysis program was utilized to conduct the FEA.The result show that(1) stress comparisons of theoretical solutions,model test and finite element analysis are satisfactory and stress results would be more conservative if the width of concrete of corrugated height is equal to horizontal panel width of web.Compared with the uniform load,the coefficient of shear lag under the concentrated load is larger.These calculation formulas are suitable to analyze the shear lag effect of the composite box girder with corrugated steel webs.