Analysis On Stress Concentration Of Grid Structure With Pipe-Welded Hollow Spherical Joints

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 hollow spherical joints has been widely studied in the static performance, the fatigue problem has little research. Stress concentration is one of the important factors that cause fatigue undermine of the component and joints.The paper used ANSYS to analyse stress concentration of grid structure with welded hollow spherical joints under uniaxial tensile, and carried out the following conclusions:1.The author used five kinds of welded hollow spherical joints model consistent with the test samples to get the rule of the stress distribution of joints.2.The paper gained the the numerical solution of stress concentration and identified the specimen in the pilot phase of the value of the load flexibility.3.Under different circumstances of d/D and t/T, the paper made a finite element analysis on the 83 kinds of matches which based on 7 kinds of welded hollow spherical to get the rule of stress concentration, which showed that pipe and hollow spherical joints stiffness differential is an important factor to impact stress concentration.Based on theoretical analysis, the paper put forward some effective measures to reduce the stress concentration of welded hollow spherical joints .