Effect of Joint Stiffness on Flexural Performance of a Hybrid FRP-Aluminum Space Truss Structure

A novel hybrid fiber-reinforced polymer (FRP)-aluminum space truss structure with pretightened teeth connections (PTTCs) and aluminum-bolt-ball connecting system (ABCS) that can be used as part of pedestrian bridges, platforms in marine areas, or roof structures is proposed. To understand the failure modes, bearing mechanism, and flexural behavior of the structure, three-point bending tests were conducted. Three loading scenarios were designed to investigate the impacts of different joint conditions. Each scenario presented different structural loading responses. Promoting the bolt stiffness and strength of ABCS improved the structural stiffness and ultimate load. The structural ductility was greatly increased by introducing joint ductility. A solid-element model of the ABCS simulated the joint loading behavior. The fine-line element structural model was established considering the joint stiffness extracted from the finite-element (FE) analysis of the ABCS model. Both models were validated by experiments.