ABSTRACT
With the promotion of grid structure, as a more reasonable form of joints,welded hollow spherical joints has been applied more and more in engineering. Although the welded holloe spherical joints has been widely studied in the static performance, the fatigue problem has little reseaech,stress concentration is one of the important factors that cause fatigue undermine of the component and joints. When hollow spherical joints is in stste of pulling, there is serious tensile stress concentration on pontes between circular steel bar and ball node. There are more serious of the tensile stress, more easily to occur ductile-brittle fracture, Therefore this region is very possible to crack first causes the welding hollow ball node to lose the bearing capacity. Ductile-brittle fracture of steel structures are a special problem, the traditional strength calculation can not solve this problem.This article uses the ANSYS finite element analysis software, taking wire table welding hollow ball connection node and semicircle building as object of study , basing on the theory of nonlinear finite element, taking ANSYS as analysis tools, using force distribution of solid element simulation nodes SOLID95 , analyzing the grid connections and welded hollow spherical body works under uniaxial tensile stress concentration.
