下承式钢管混凝土拱桥稳定性研究  

Investigation of Stability of Through CFST Arch Bridges

作　　者：邢帆[1] 祝兵[1] 王学勇[1] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《桥梁建设》2009年第1期25-28,共4页Bridge Construction

摘　　要：以某下承式钢管混凝土拱桥为工程背景,对成桥阶段自重作用下结构的稳定性进行研究。在线弹性稳定分析中,使用4种方法对拱肋结构刚度进行模拟,所得的稳定系数随拱肋计算刚度而不同,且变化幅度较大。建议把失稳分析同变形计算结合考虑,并偏安全地取较小的稳定系数。在非线性稳定分析中,采用钢管混凝土统一理论来考虑拱肋的材料非线性,并引入几何缺陷的影响。双非线性分析表明拱肋的几何非线性效应不明显,引起结构失稳的主要因素是材料非线性。Backgrounded by a through concrete-filled steel tube （CFST） arch bridge, the structural stability of the type of the bridges under the action of self weight at completion stage is investigated. In the linear elastic stability analysis, four kinds of methods are used to simulate the structural rigidity of the arch ribs of the bridges. The obtained stability coefficients vary with the calculated rigidity of the ribs and the variation range is considerably great. It is therefore proposed that the instability analysis should be made in consideration of the deformation calculation and the smaller stability coefficients should be selected for the sake of safety concern. In the nonlinear stability analysis, the unified theory of the CFST is used to take into account of the nonlinearity of materials of the ribs and the influences of the geometric defect are introduced. The dualnonlinear analysis reveals that the geometric nonlinear effect of the ribs is slight and the principal factor that will cause the instability of the structures is the nonlinearity of materials.

关 键 词：下承式桥 钢管混凝土拱桥 有限元法 稳定分析 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] TU311.2[交通运输工程—道路与铁道工程]