平面外弯矩作用下T形圆管节点热点应力分布

Hot Spot Stress Distribution of CHS T-joints under Out-of-plane Bending

确定钢管相贯节点热点应力沿相贯焊缝的分布情况是计算热点应力极值的基础.对平面外弯矩作用下的T形圆管相贯节点焊缝处热点应力分布开展研究,并提出了其应力分布曲线方程.利用径向拉伸法建立了T形圆钢管相贯节点的有限元网格模型,对焊趾处热点应力分布的计算结果进行了可靠性分析,并将三种不同密度网格模型的应力分析结果进行对比.结果表明,基本网格密度可满足计算精度要求.利用经试验验证的有限元模型分析了T形圆钢管相贯节点在平面外弯矩作用下的热点应力沿相贯线的分布规律,考查了四个无量纲几何参数对应力分布曲线形状的影响,在此基础上拟合并确定了基于三角正弦函数的曲线修订公式.经与UCL公式和试验数据对比分析,表明本文公式具有更高的精度.

Determining the hot spot stress distribution along the intersecting weld of a tubular joint is the basis for calculating the peak value of hot spot stress.The study on the hot spot stress distribution along the intersecting weld of circular hollow section(CHS)T-joints is carried out and a stress distribution curve equation under out-ofplane bending moment is proposed.The finite element mesh model of CHS T-joints is established by the radial tension method.The reliability of the calculation results of hot spot stress distribution at the weld toe is analyzed.The stress analysis results of three mesh models with different mesh densities are compared,which shows that the basic mesh density meets the requirements of calculation accuracy.The hot spot stress distribution along the intersection line of CHS T-joints under out-of-plane bending moment is analyzed,utilizing experimentally validated FEA models,and the effects of four dimensionless geometric parameters on the shape of stress distribution curve are investigated.On this basis,the curve revision formula based on trigonometric sine function is proposed and determined.The statistical analysis compared with the UCL formula and experimental data shows that the formula proposed in this paper has higher accuracy.