斜腹式、鱼腹式箱梁剪应力计算

针对目前应用越来越广泛的斜腹式、鱼腹式箱梁,阐述了其剪应力计算不同于矩形截面梁的地方,并指出其剪应力计算不符合传统的矩形截面梁剪应力计算的假定。针对上述问题,分别采用平面梁单元和空间块体单元对拟定的斜腹式、鱼腹式箱梁截面的剪应力进行计算对比。结果表明,采用传统的矩形截面梁的剪应力计算公式来计算斜腹式、鱼腹式箱梁腹板上的剪应力,结果将有较大的误差。为此,提出了腹板抗剪有效厚度的概念,为斜腹式、鱼腹式箱梁剪应力计算提供了一个简便的、可行的方法。

Shear Stress Computation of Box Girders with Oblique web or Fish-bellied Web

This article sets forth the shear stress computation of the box girder with oblique web or fish-bellied web being more and more widely used now different from the rectangular section girder,and points out that its shear stress computation falls short of the shear stress computation of the traditional rectangular section girder.Aiming at the above problems,the plane girder unit and the spatial block unit are separately used to calculate and compare the shear stresses of the proposed oblique web or fish-bellied web box girder sections.The result shows that the error will be larger if the traditional shear stress calculation formula of rectangular section girder is used to calculate the shear stress on the oblique web or fish-bellied web box girder.Therefore,the conception of efficient anti-shear thickness of web is put forward and provides a simple and feasible method for the shear stress computation of box girder with oblique web or fish-bellied web.