方管圆管混合空间钢管节点承载性能的非线性分析

以圆管为弦管,方管(包括矩形管)为支管的混合空间钢管节点,构造新颖,受力复杂,其承载力设计和计算是工程师所关注和急需解决的问题。本文采用非线性有限元方法,选用四节点等参壳元,应用自动步长增量法求解方管圆管混合空间管节点轴向受力或平面外受弯的极限承载力。程序系统在移植ADINA程序的基础上,开发了可进行T型、X型、K型和TT型管节点有限元网格剖分的前处理程序CTUBE,并编写了AutoCADADS/RX应用程序显示管节点模型受荷后的变形和应力分布。本文通过大量算例分析,回归出相关承载力计算公式,供设计人员参考。

Nonlinear analysis for the bearing properties of multiplanar tubular joints with square and circular hollow sections

The hybrid multiplanar tubular joints with circular tubes as the chords and square tubes(including rectangular tubes) as the braces are newly constructed and in complex stress conditions. The design and calculation of the joint loading capacity are concerned by engineers and need to be solved. This paper employed nonlinear finite element method, used a four node isoparametric shell element, and presented an algorithm for automatic incremental solution to solve the ultimate strength of multiplanar tubular joint with square and circular hollow sections subjected to axial loading or out of plane bending. Based on the transplant of ADINA program, a pre processing program named CTUBE was developed to generate the finite element mesh of T joints, X joints, K joints and TT joints. And a program based on the AutoCAD ADS/RX was composed to display the deformed shapes and the stress distributions of the loaded joints. The formulae to calculate the loading capacity were obtained through regression analysis of plenty of examples. This study can be used as a reference for those engaged in the design and research of such kind of joints.