Failure Pressure of Welded Hollow Spherical Joints Containing Grooving Corrosion Defects and Wall Reduction

Welded hollow spherical joints (WHSJ) have been widely used in various space structures. Corrosion of WHSJ is inevitable and will eventually threaten the structural safety. This paper makes an assessment of the accuracy of quality inspection procedures commonly employed by spatial grid structure to calculate the failure pressure of corroded WHSJ via finite element analyses (FEA). Second, this paper studies the influence of the corrosion depth, corrosion pattern, groove height, joint size and other parameters on the bearing capacity of WHSJ also via FEA. Analytical procedures to calculate the failure pressure associated grooving corrosion are not available yet. Thus, based on the parametric analysis results, such a procedure is devised and proposed here. Results indicated that the wall thickness loss and the diameter ratio were the main factors affecting the ultimate compressive performances of WHSJ; the volume loss of WHSJ outside the "critical latitude of groove" had nothing to do with the compressive performances; the influence of corrosion on the ultimate compressive performances was independent of the diameter and thickness of WHSJ. The derived result would lay a foundation for the prediction and evaluation of the residual bearing capacity of space grid structures with WHSJ.