作　　者： ;

机构地区： 佛山科学技术学院环境与土木建筑学院土木工程与建筑系

出　　处： 《铁道学报》 2008年第1期48-52,共5页

摘　　要： 下承式钢桁结合梁桥是适合高速铁路的桥梁结构形式之一,由于受力复杂,难以直接确定其在荷载作用下的精确解析解。本文根据下承式钢桁结合梁的变形特征,将其进行连续化处理,等效为闭口薄壁组合箱形梁。然后用势能驻值原理导出下承式钢桁结合梁考虑桥面系钢纵梁-混凝土板相对滑移、横梁竖向变形的影响和混凝土板剪滞效应的控制微分方程。根据结构在双线对称荷载作用下的受力特点,假设等效闭口薄壁组合箱形梁的位移函数,求出下承式钢桁结合梁的近似解。利用本文方法对一个4节间简支下承式钢桁结合梁试验模型进行结构的位移和应力计算。通过将本文解与试验结果对比,说明本文公式的正确性。 Through steel-truss composite beams are considered one of the ideal structure types of high-speed railway bridges. Because of their complex mechanical behaviours, it is difficult to determine their accurate analytic solutions when they are under the action of loads. Through steel-truss composite beams were treated continuously and were made equivalent to closed thin-walled composite box beams by means of the deforming features of the structure. Then the governing differential equations of the structure in consideration of the relative slip between longitudinal beams and concrete slabs on the bridge deck, vertical deformation of transverse beams and shear lag effect on concrete slabs were deduced with the minimum potential energy principle. In terms of the mechanical behaviours of the structure under the action of double-track symmetry loads and the assumption of the displacement functions of equivalent closed composite box beams, the approximate solution to through steel-truss composite beams was obtained. The displacements and stresses of a simple-support through steeltruss composite beam model with four spaces were calculated by means of the proposed method. It shows the exactness of this paper＇s formulae by comparing the proposed method solutions to the test results.

关 键 词： 下承式钢桁结合梁 连续化处理 相对滑移 剪滞效应 近似解

领　　域： [建筑科学] [交通运输工程]