残余应力对桥梁波形钢腹板屈曲性能的影响

Influence of Residual Stress on Buckling Performance of Bridge Corrugated Steel Webs

以一座1200型波形钢腹板桥梁为研究对象,基于有限元软件建立了考虑残余应力的波形钢腹板数值分析模型,以此来研究残余应力对桥梁的波形钢腹板屈曲性能影响。考虑残余应力对波形钢腹板屈曲性能的影响情况,通过分析波形钢腹板的厚度、长高比以及钢材强度变化,提出了考虑残余应力时波形钢腹板极限屈曲荷载的简化计算方法。研究结果表明:残余应力降低了波形钢腹板的极限屈曲荷载,使得波形钢腹板在屈曲后破坏速度加快;随着厚度及钢材强度的增大,波形钢腹板屈曲极限荷载对残余应力的敏感程度呈增大趋势;随着长高比的增加,波形钢腹板屈曲极限荷载对残余应力敏感程度呈减小趋势;可采用折减系数法来计算焊接残余应力对波形钢腹板屈曲性能的影响。

A numerical analysis model of corrugated steel web considering residual stress was established based on finite element software for a 1200-type corrugated steel web bridge,in order to investigate the impact of residual stress on the buckling performance of corrugated steel webs of bridge.Considering the effect of residual stress on the buckling performance of corrugated steel webs,the simplified calculation method for the ultimate buckling load of corrugated steel webs considering the residual stress was proposed by analyzing the thickness,length-to-height ratio and the change of steel strength of the corrugated steel webs.The research results indicate that the residual stress reduces the ultimate buckling load of the corrugated steel web,which accelerates the failure speed of the corrugated steel web after buckling.As the thickness and steel strength increase,the sensitivity of the ultimate buckling load of the corrugated steel web to the residual stress shows an increasing trend.As the length-to-height ratio increases,the sensitivity of the ultimate buckling load of the corrugated steel web to the residual stress shows a decreasing trend.The reduction coefficient method can be used to calculate the effect of welding residual stress on the buckling performance of corrugated steel webs.