基于正交试验设计的钢-混组合桥面系参数敏感性分析

Sensitivity analysis of system parameters for steel-concrete composite deck based on orthogonal experimental design

利用大型有限元软件Workbench,建立某大跨悬索桥钢-混组合桥面系节段有限元模型,基于正交试验设计了多种组合桥面系方案,计算了自重作用下组合桥面系的挠度及应力,利用直观分析和方差分析法对构造参数进行了敏感性分析。结果表明:自重作用下组合桥面系的最大挠度出现在钢桁架上,混凝土桥面板厚度及钢桁架高度变化对最大挠度有显著影响,减小桥面板厚度或增加钢桁架高度有利于减小组合桥面系的挠度;混凝土桥面板厚度、混凝土弹性模量及钢纵梁腹板高度对钢梁最大等效应力影响显著,最大等效应力随着混凝土桥面板厚度及混凝土弹性模量的增大而增大;混凝土弹性模量的变化引起的混凝土板最大拉应力的变化最大。

The finite element model of the steel-concrete composite deck system of a long-span suspension bridge is established by using the large-scale finite element software Workbench.The multi-combination deck systems are designed by orthogonal test method.The deflection and stress of the composite deck system under the dead weight are calculated,and the sensitivity analysis of the structural parameters is carried out by visual analysis and analysis of variance.The results show that,the maximum deflection of composite deck system occurs on steel truss under the dead weight,the thickness of concrete deck,the elastic modulus of concrete and the height of steel truss have a significant influence on the maximum equivalent stress.The maximum equivalent stress increases with the increase of the thickness of concrete deck and the elastic modulus of concrete.The change of the elastic modulus of concrete leads to the biggest change of the maximum tensile stress of concrete slab.The research result can provide reference for future design of steel-hybrid composite deck system.