Design method and experimental investigation of compression members in a space structure strengthened by folded sleeves

Abstract

The compression member strengthened by the sleeve can effectively enhance the bearing capacity. In this paper, the calculation equation for the contact force between the core and the outer sleeve is deduced, and a bolt design suggestion of the folded sleeve is provided. The test results show that the peak load of the folded sleeve member is increased by over 55.3%. When the number of bolted regions of the folded sleeve increases, the peak load only slightly increases. There are two failure modes of folded sleeve members, including the global buckling and the end bending of the unrestrained segment of the specimen. The number of bolted regions of the folded sleeve has minimal influence on the failure mode. The performance of the folded sleeve is better than that of the assembled sleeve and similar to that of the seamless sleeve. The Abaqus numerical model of the specimen is established and can effectively simulate the mechanical properties of folded sleeve member. The comparison between the theoretical and numerical simulation results of the contact force shows that the theoretical calculation equation of contact force has high safety. Based on the experimental and numerical simulation results, the safety factor, λ, of the bolt spacing of the folded sleeve member is defined.