单向及双向荷载作用下加劲曲板极限承载力研究

Ultimate Load Bearing Capacity of Stiffened Curved Panel underUniaxial and Biaxial Loads

为了解复杂受力状态加劲曲板的受力性能,以西堠门公铁两用大桥主桥钢箱梁腹板为背景,考虑几何非线性、材料非线性和初始缺陷,采用有限元法分析单向受压及双向荷载(压-压、拉-压)作用下加劲曲板的极限承载力,研究极限承载力随关键设计参数(曲线半径、加劲肋刚度比、肋间子板宽厚比及母板长宽比)的变化规律。结果表明:在单向受压作用下,加劲曲板的极限承载力基本不随设计参数的变化而变化,双向荷载作用下加劲曲板的极限承载力会随横向力的增加而降低,通过增大曲线半径、加劲肋刚度比可提高加劲曲板双向荷载作用下的极限承载力,通过降低肋间子板宽厚比、母板长宽比可提高加劲曲板压-压作用下的极限承载力。

This study focuses on the load bearing behavior of stiffened curved panels(SCPs)under complex loading conditions.Based on the webs of the steel box girders in the main bridge of Xihoumen Rail-cum-Road Bridge,finite element modelling was conducted to analyze the ultimate load bearing capacity(ULC)of the SCPs under uniaxial and biaxial loads(compression-compression,tension-compression),respectively,considering the geometric linearity,material linearity and initial defects.The relations between the ultimate load bearing capacity and key design parameters(curvature radius,relative stiffness of stiffeners,width-to-thickness ratio of the subpanel between stiffeners and aspect ratio of base panel)were investigated.The results show that under uniaxial loads,the ULC of SCPs does not fluctuate along with the variation of design parameters,but falls with the increasing of lateral forces under biaxial loads.Enlarging the curvature radius of the SCPs and improving relative stiffness of stiffeners can enhance the ULC of the SCPs under biaxial loads,while reducing the width-to-thickness ratio of the subpanel between stiffeners and aspect ratio of base panel lead to the improved ULC of the SCPs under compression-compression loading.