大跨径自锚式悬索桥主缆位移特性分析  

Displacement characteristics analysis on the main cable of large-span self-anchored suspension bridge

作　　者：王桢[1] 吴海军[2,3] 周志祥[2,3] 王身宁 

机构地区：[1]中交第一公路勘察设计研究院有限公司,陕西西安710075 [2]重庆交通大学,重庆400074 [3]山区桥梁与隧道工程国家重点实验室培育基地,重庆400074

出　　处：《土木工程学报》2015年第7期102-111,共10页China Civil Engineering Journal

基　　金：交通运输部行业联合科技攻关项目(2010-353-341-230)

摘　　要：针对大跨径自锚式悬索桥的主缆位移特性问题,采用理论计算分析与全桥模型试验相结合的方法,研究大跨径自锚式悬索桥主梁脱架前后主缆位移的相干性,分析施工阶段和成桥阶段主缆位移的几何非线性特征,揭示结构体系转换对主缆位移的影响。结果表明:主缆位移的弱相干性仅适用于主梁完全脱架前;在施工阶段,主缆位移的几何非线性行为主要经历线性特征显著、非线性特征增强、非线性特征弱化、线性化趋势明显的四个阶段;影响线零点表现出比其他主缆位置更为明显的几何非线性特征,且随着工况增加,不断向张拉点靠近并最终与其相邻;结构体系转换对主缆位移几何非线性特征的影响强烈;主缆的垂跨比对主缆位移几何非线性特征强弱的影响是不容忽视的;在成桥阶段,在结构恒载作用下,主缆位移线性化趋势更加明显。The main cable displacement characteristics of a large-span self-anchored suspension bridge are studied by both theoretical calculation and the total bridge model tests. The displacement coherence of main cables before and after support dismantling,the geometric nonlinear displacement characteristics of main cable in construction and finished stage are analyzed. The influence of structural system transformation on displacement of main cable is presented. The analysis results show that the weak coherence of the main cable is effective only when the girder support is not completely dismantled. The geometric nonlinear behavior of the main cable in construction stage can be divided into 4 phases（ i. e.,linear distinct features,enhancing nonlinear features,weakening nonlinear features and obvious linearization trend）.The null point of influence line,which gets close to the tension point as construction process continues,shows more obvious geometric nonlinear features than the rest parts of the main cable. The geometric nonlinear features of main cable are influenced by the structure system transformation and the intensity of the nonlinearity is affected by sag-span ratio. In the finished stage,the displacement of main cable under the dead load shows an obvious linearization trend.

关 键 词：自锚式悬索桥 主缆位移特性 全桥模型试验 弱相干性 几何非线性 结构体系转换 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] TU317.1[交通运输工程—道路与铁道工程]