横隔板对波形钢腹板组合梁翼缘有效宽度影响研究

Research on the effect of Diaphragm on The Effective Flange Width of Composite BoxGirder Bridges with Corrugated Steel Webs

为研究横隔板对波形钢腹板组合梁翼缘有效宽度的影响,通过有限元法研究横隔板厚度对截面翘曲变形的影响,以及跨间横隔板对组合梁翼缘有效宽度的影响。针对支点处横隔板,提出在波形钢腹板组合梁剪力滞效应微分方程的基础上,通过引入广义位移函数边界条件,计算其对翼缘有效宽度影响的方法;并与有限元法、不考虑横隔板作用的分析方法以及基于单广义位移函数的分析方法进行对比。结果表明:横隔板对截面翘曲变形的约束能力随着横隔板刚度的增加而增强;横隔板对组合梁翼缘有效宽度的影响仅存在于横隔板位置附近,而通常情况下,跨间横隔板厚度较小,可不考虑其影响;所提方法得到的组合梁翼缘有效宽度与有限元结果吻合良好,与另外两种方法相比具有更高的精度。

To study the effect of diaphragm on the effective flange width of composite girder with corrugated steel webs,the effect of diaphragm thickness on section warping deformation and the effect of cross-span diaphragm on flange effective width of composite beam are studied by finite element method.In addition,based on the differential equation of shear lag effect of composite beams with corrugated steel webs,a method was proposed to calculate the effect of diaphragm at the support on the effective flange width by introducing boundary condition of generalized displacement function,and the proposed method is compared with the finite element analysis,the method being unable to consider the effect of the diaphragm,and the method based on the single generalized displacement functions.The research presented in this paper shows that the restraining ability of the diaphragm to the warping of the section increases with the thickness of the diaphragm.The effect of diaphragms on the effective flange width of composite beams only exists near the diaphragms.In general,due to the small thickness of the diaphragms between spans,the effect is negligible.The effective flange width of the composite beam obtained by the proposed method is agree well with the finite element analysis,and it has higher accuracy than the other two methods.