单索面斜拉桥混凝土宽箱主梁受力特性分析

分析单索面斜拉桥混凝土宽箱主梁受力的特殊性,采用空间网格模型对垒水河桥进行结构分析,明确其主梁的板效应和剪力滞效应。由于单索面拉索的支撑作用,故箱梁内侧竖向变形较外侧小,内力较外侧大;独柱墩处近拉索侧腹板顶剪力滞效应最大,剪力滞系数高达2.7;独柱墩处截面的外侧腹板顶、挑臂顶和38 m跨边支点附近截面的中间底板处出现负剪力滞系数,这与初等梁理论的计算结果有根本的区别。

Analysis on Mechanical Characteristics of Concrete Wide Box Girder of Single-Plane Cable-Stayed Bridge

The special characteristics of the concrete wide box girder of single cable-stayed bridge are analyzed.The structural analysis of the bridge is carried out by using the spatial grid model,and the slab effect&shear lag effect of the main girder are clarified.Because of the support function of single cable,the vertical deformation inside the box girder is smaller than the outer side and the internal force is larger than the outside;the shear lag effect of the web top near the cable side of the single column pier is the largest,and the shear lag coefficient is as high as 2.7;the negative shear lag coefficient appears at the top of the outer web,the top of the cantilever and the middle bottom of the section near the side fulcrum of the 38 m span at the single column pier,which is fundamentally different from the calculation results of the elementary beam theory.