网架焊接空心球节点残余应力实测及数值模拟

为了研究焊接空心球节点中管球连接焊趾处残余应力的分布规律和数值大小,采用盲孔法对球面焊趾和管面焊趾处的焊接残余应力进行测定。得到焊接残余应力数值大小和分布规律。并采用Visual-Environment有限元模拟软件得到焊缝处温度场和残余应力场,以及残余应力分布曲线。结果表明:焊接残余应力在整个焊接空心球节点上呈周期性、随机性的特点,两者规律性吻合良好。同时,由有限元分析结果可知球面及管上均存在残余拉应力及残余压应力,并且在整个试件上焊接残余应力处于自平衡状态。研究结果将为后续研究焊接空心球节点网架结构的疲劳性能奠定基础。

Blind hole method and finite element analysis* of the residual stress distribution law near the weld of the hollow sphere node of the mesh frame welding

To study the distribution law and numerical size of the residual stress at the toe of the tube ball weld in the welded hollow ball node, this paper uses the blind hole method to determine the weld residual stress at the spherical toe and the tube surface toe of the weld of the welded hollow ball tube-ball butt weld. Through the test measurement, the spherical toe and tube surface weld toe welding residual stress at the size of the value and distribution law. And the use of Visual-Environment finite element simulation software to get the weld at the temperature field and residual stress field results, as well as the overall component residual stress distribution curve. Through the test and finite element results show that the welding residual stress is periodic and random throughout the welded hollow sphere node. At the same time, the finite element results show that there are residual tensile stresses and residual compressive stresses on the sphere and tube, and the welded residual stresses are in a self-balancing state with no external stress performance on the entire component. This paper test and simulation data for the fatigue properties of welded hollow sphere nodes and other material properties, mechanical properties of research to provide support and reference.