架设阶段悬索桥静力问题的随机有限元分析

架设阶段的悬索桥不仅具有显著的几何非线性行为，而且存在材料特性的变异。本文建立了以增量形式表达的非线性摄动法随机有限元列式，并编制了悬索桥静力分析程序ＳＮＡＰ。针对一座国内在建的悬索桥，计算了该桥在某一施工阶段考虑缆索弹性模量随机性时主梁跨中点位移的变化。结果表明，材料随机性的影响十分明显。

Static analysis for suspension bridges under construction based on SFEM

At the construction stage, suspension bridges not only have significant geometric nonlinearity behavior, but also possess variation of material. Based on the perturbation method, an analytical method of the static problems of long span suspension bridges is presented in this paper. An incremental formulation is established for the nonlinear stochastic finite element method SFEM of static problems, which can involve in the geometric nonlinearity such as large displacement and beam column effect. As an example, the midspan deflection of a long span suspension bridge under construction is analyzed when the elastic modulus of the cables is assumed to be correlated random variables. Numerical results show that the material randomness has a significant effect on the midspan deflection.