桥梁半平行钢丝索对称断丝的力学特性分析  

Mechanical Properties Analysis of Semi Parallel Wire Cables for Bridges with Symmetric Wire Breaks

作　　者：彭崇梅[1,2] 张启伟[1] 李元兵[2] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]同济大学桥梁工程系,上海200092

出　　处：《同济大学学报（自然科学版）》2013年第4期496-502,共7页Journal of Tongji University:Natural Science

基　　金：国家自然科学基金(50978199)

摘　　要：桥梁用半平行钢丝索由于外层钢丝的螺旋外形和本身构造的特殊性,不能直接应用基于平行钢丝假定的并联模型或钢绞线模型进行力学分析.基于Love曲杆理论,考虑泊松效应、钢丝间接触变形以及钢丝间的接触力和摩擦力的影响,对多层半平行钢丝索的对称断丝模型进行了修正,通过数值计算讨论了拉索截面钢丝拉力分布规律、钢丝拉力增长系数和拉索轴向刚度及其影响因素.计算表明,考虑接触变形后,截面内钢丝拉力分布不均匀,拉索轴向刚度较单根钢丝有较大幅度的下降.Strands model or parallel model based on the assumption of parallel wire is helpless to semi parallel wire cable for its helical characteristics and complex structure. Based on the theory of Love＇s curved bar, the mechanical model for multilayered semi parallel wire cables with symmetric wire breaks is updated with a consideration of the effects of the Poisson＇s ratio and contact deflection between wires, inter-wire contact force and friction. Axial force distribution of wires, magnification factors of axial force and axial stiffness of the cable are discussed by numerical calculation. Numerical examples show that the contact deformation aggravates axial force nonuniform distribution of wires and that the axial stiffness of cables falls much after the wire breaks.

关 键 词：钢丝索 对称断丝 接触变形 轴向刚度 

分 类 号：U443.38[建筑科学—桥梁与隧道工程]