Influence of welded hollow spherical joints on the mechanical behavior of single-layer reticulated shell structures

Abstract

Welded hollow spherical joints (WHSJ) are widely used in space lattice structures. Beam models are widely adopted in analyzing integral structures for high computational efficiency. However, the influence of WHSJ cannot be estimated accurately, and few studies on the accuracy of beam models are available. Numerical models in different scales were established, and results derived from different models were compared to investigate their accuracy. Results indicated that the influence of WHSJ on the mechanical behavior of integral structures varies along with its scale. A large error may exist in the results obtained by the beam models, especially for the models with thick pipe and thin WHSJ. The largest error in ultimate strength is 250% when components were meshed into one beam element, and the minimum error of results derived from the beam model is approximately 10% when components were meshed by a sufficient number of elements. Results derived from multi-scaled models agree well with the results derived from the refined model.