Abstract:
Fiber reinforced polymer (FRP) pultruded profiles can be directly used as emergency bridge load-bearing girders to overcome small and medium span obstacles. To realize the longitudinal 'beam-beam' connection of the girders, this study proposes a GFRP square tube connection node (BB-PTC) based on pre-tightened tooth connection. The full-scale specimens of the connection were prepared, and the cantilever bending tests were carried out to obtain the bearing performance response, bearing capacity and failure mode of the connections under different bolt preload and, jack supporting and through bolt settings. Based on the double-ellipse progressive damage material model of FRP pultruded profiles, the material Vumat for explicit dynamic analysis was compiled, and the bearing capacity of FRP multi-tooth connects was numerically simulated to verify the mesh sensitivity, numerical stability and, calculation accuracy of the material model. The finite element model of BB-PTC connection is established by using the progressive damage material model. The results show that the connection model can accurately simulate the bending mechanical response of the joint and accurately predict the ultimate bearing capacity and failure mode of the joint. Finally, compared with the bolted ' beam-beam ' joint, the BB-PTC joint realizes the bending moment transmission at the end of the GFRP beam by combining the preload with the shear resistance of the tooth body, and it has higher bearing efficiency and connection stiffness.