钢筋混凝土连续曲线箱梁桥剪力滞效应研究

A Study on Shear Lag Effect for Continuously Curved RC Box Girders

针对连续曲线箱梁桥的结构形式,重点研究了钢筋混凝土连续曲线箱梁桥的剪力滞效应。通过运用大型有限元通用软件AN SY S,对不同因素变化下的钢筋混凝土连续曲线箱梁桥进行建模分析。在实桥荷载试验的基础上,计算各种工况作用下箱梁梁体的挠度、应变应力及剪力滞系数值;分析曲率半径等因素对曲线箱梁剪力滞效应的影响。研究结果表明曲率半径对连续曲线箱梁的剪力滞效应有较大影响,因而在曲线箱梁的设计中应加以考虑。

The finite element method is applied to analyze the shear lag effect of continuously curved RC box girders. The affecting factors include： curvature radius, ratio of height to width, distance of webs, bearing offsetting of single-pedestal pier, numbers of cross boards and forms of beam section. Based on the load testing in a real bridge, the deflection, strain, stress and shear lag coefficients are calculated . The rules of shear lag coefficients changing with the affecting factor are summarized. It is proved that curvature radius is the most important affecting factor and the suggestions on diminishing the shear lag effect in design are made.