Prefabricated tubular light roof truss assembled with screwed novel modular connectors: Full-scale test and FE modelling

A new system for prefabricated light-steel roof truss composed of thin-walled square hollow section (SHS) members assembled with a kind of U-shape screwed novel modular connectors is proposed in this paper. The novel modular connectors are suitable for fastening SHS members of various sizes under different loading conditions and can easily be assembled by self-drilling screws with ensured structural integrity and rigidity. The design and assembling of a 33.4 m single span roof truss in such form were introduced in detail and the full-scale test was carried out to verify its structural performance by means of the bearing capacity, stiffness and failure mode. Finite element analysis was performed on structural level considering different rigidity of the joints on the mechanical response of the roof truss. Fine numerical modelling of typical joints was also conducted to evaluate the bearing capacity and failure mode of the novel modular connector. Both the full-scale experimental study and the two-level numerical investigation demonstrated that the proposed roof truss system was in the elastic stage and the connector was reliable during the loading process.