矩形钢管偏心相贯节点的平面外抗弯刚度

Out-of-plane flexural rigidity of unstiffened eccentric rectangular hollow section joints

为了获得十字形矩形钢管偏心相贯节点的平面外抗弯刚度,本文采用理论模型结合数值分析的方法,基于塑性铰线模型和节点变形特征,建立了用于节点抗弯刚度计算的三梁系模型,结合参数分析和回归分析,获得节点刚度参数化计算式。结果表明:节点刚度与主管壁厚三次方成正比、与支管宽度与主管高度之比呈线性关系、与支主管高度比近似指数函数关系,计算式所得节点抗弯刚度值与有限元结果的差异大部分小于10%。

This work applied a theoretical model method combined with numerical analysis to establish a practical parameterized calculation formula for the out-of-plane flexural rigidity of unstiffened eccentric cross-type rectangular hollow section (UECRHS) joints.A three-beam model for calculating the elastic out-of-plane flexural rigidity of UECRHS joints was established on the basis of a yield line model and the connection deformation characteristic.Then,the theoretical formula for rigidity was established and corrected in accordance with the parametric analysis results from finite element (FE) analysis.A practical parameterized calculation formula for the out-of-plane flexural rigidity of UECRHS joints was obtained through multivariable nonlinear regression analysis.Results showed that rigidity was directly proportional to the cube of chord thickness,was linearly related to the brace width-to-chord depth ratio,and had a nearly exponential function relationship with the brace-to-chord depth ratio.Moreover,the relative errors between the out-of-plane flexural rigidity values obtained by the formula and FE results were mainly less than 10%.