基于多参数翘曲位移函数的箱梁剪力滞和剪切效应分析解析法

Energy-variational method for both shear lag and shear deformation effects in thin walled box girder based on the warping displacement function with three parameters

用多参数翘曲位移函数考虑箱梁截面底板、顶板、悬臂板剪滞翘曲幅度一般各不相同的影响,计入箱梁剪切变形,导出了箱梁剪滞效应分析的控制微分方程组、边界条件及相应的闭合解。给出了算例结果,表明此方法用于求解薄壁宽箱梁的应力和挠度能大幅度提高计算精度。此方法蜕化后可广泛用于多种常见桥梁结构剪力滞效应的高精度分析。

In the paper, the shear lag effect in box girders is studied by means of a warping displacement function with three parameters for the consideration of different warping amplitude of upper plate, floor plate and projecting slab. Furthermore, the shear deformation is taken into account, and the governing differential equations, boundary conditions and the closed-form solutions for calculation of shear lag effect in box girder are deduced. The calculation results of the example quoted make it clear that the precision can be improved to a great extent in calculating the stress and deflection of thin-walled box girder. The method proposed in this paper is also suit for calculation of the shear lag effect in multiform common bridge structure by changing some parameters in the formula proposed in the paper.