Structural design and compression-bending test of ultra-lightweight carbon-fiber-reinforced polymer truss structures

Based on the ultra-lightweight, large-span, and heavy-load structural design requirements for the load-bearing structure of next-generation spacecraft, the ultra-lightweight structure design, modular integration technology and joint construction pattern of carbon-fiber-reinforced polymer (CFRP) truss structures are systematically studied herein, and an ultra-lightweight full-scale CFRP composite truss structure is proposed. The truss module can be separately designed for structural pattern based on the force characteristics and functional requirements, which enhances the freedom of structural design. Using developed self-equilibrium test equipment, the compression-bending behavior of the two novel 1:1 full-scale CFRP truss structure prototypes with spans of 20.4 m (A-Truss and B-Truss) are experimentally studied. The failure mode of the truss structure is analyzed, the reasons for the failure of the joints are identified, and the corresponding improvement measures for the joint failure position are proposed and verified through tests. The designed ultra-lightweight CFRP truss structure prototype meets four design specifications in terms of bearing capacity and deformation, solving the ultralightweight structure design issue of truss structures and realizing the large-span, ultra-lightweight, and heavy-load structural design goals.