蝶形拱桥的非线性行为分析  

Analysis on Nonlinear Behavior of Butterfly-shaped Arch Bridge

作　　者：霍学晋[1] 韩立中[1,2] 

机构地区：[1]清华大学土木水利学院,北京100084 [2]交通运输部公路科学研究院,北京100088

出　　处：《公路交通科技》2013年第9期53-60,共8页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金重点项目(51138007);国家科技支撑计划项目(2011BAJ09B02)

摘　　要：蝶形拱桥由于拱肋外倾其非线性行为规律较之普通拱桥更加难以掌握,传统未充分考虑非线性影响的设计方法已不再适用。在自编程序的基础上,全面分析了各种非线性因素对蝶形拱桥外倾拱和3类索非线性行为的影响及规律。结果表明:相对主梁单元,拱肋单元的梁柱效应对拱顶横向位移的影响较大;恒载工况下,面外弯矩的影响系数呈波浪形变化;计算拱肋轴力时可忽略非线性因素的影响;考虑全部非线性因素后主吊索力的非线性影响系数由长索向短索递增,影响系数与索力值成反比;相对主梁单元,拱肋单元的梁柱效应对斜拉索和副吊索索力的影响较大。As the arch ribs of butterfly-shaped arch bridge are outward inclined, the nonlinear mechanical behaviors are difficult to master compared with ordinary arch bridges, traditional design method which does not fully consider nonlinear influence is not applicable. On the basis of self-compiled program, the influence of different nonlinear factors on the nonlinear behaviors of inclined arches and 3 kinds of cables of the bridge and the regularity are comprehensively analyzed. The results show that （ 1 ） the influence of beam-column effect of arch rib elements on the lateral displacement at the apex of arch ribs is greater compared with that of main girder elements; （2） the influence coefficients of outer bending moment present a wave distribution under dead load; （3） all nonlinear factors can be neglected when calculating the axial forces of arch ribs; （d） when all nonlinear influencing factors are considered, the nonlinear influence coefficients of main cable forces increase progressively with cable length decreases, therefore they are inversely proportional to the values of cable forces ; （5） the beam-column effect of arch-rib elements has greater influence on the forces of stay cables and subsidiary cables compared with that of main girder elements.

关 键 词：桥梁工程 非线性行为 增量迭代法 蝶形拱桥 大位移 梁柱效应 索的垂度 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]