Abstract: Based on theory of structural stability，the solution procedure and principle of finite element method are introduced in brief under the analysis of structural stability．With the finite element analysis．the stability of the tower is studied by taking the cable—hoisting erection system of the Wujiang River Bridge in the Pengshui City as engineering background．Through multlvle solution by iterative method．the critical load factors and buckling mode shapes of the tower are obtained under the most disadvantageous construction work condition，providing theories foundation for the construction control of that bridge．

Key words: long-span arch bridge, cable·hoisting erection system, finite element analysis of stability, critical load factors, buckling mode shapes

摘要： 基于结构稳定理论，介绍了在结构稳定性分析中有限单元法的求解原理及求解过程．以彭水乌江大桥缆索吊 装系统为工程背景，考虑起吊、运输等状态，及风荷载，按塔架的最不利受力组合进行分析，对其塔架的稳定性进行 有限元分析，通过多次迭代求解得出了该吊装系统在最不利施工工况下塔架的屈曲临界荷载系数和失稳模态，为该 桥的施工控制提供了理论基础．

关键词: 大跨度拱桥, 缆索吊装系统, 有限元稳定性分析, 临界荷载系数, 失稳模态