Structural performance evaluation of pultruded GFRP composite space truss: Experimental study and numerical simulation

This paper presents space truss structures assembled from pultruded square hollow glass fiber reinforced plastic (GFRP) members. The novel steel connectors are used to connect the GFRP members, which can significantly improve construction efficiency. The structural performance of the four-span space truss and space truss unit is evaluated by the four-point bending test and the static test, respectively. The test results show that the GFRP space truss structure exhibited satisfactory overall stiffness and load-bearing capacity. The failure modes mainly include shear failure of the bolt, local buckling of GFRP profiles, and local cracks at holes and cuts. The structural stiffness of the space truss unit increases at the post-failure stage, which is caused by the compression buckling of the pultruded GFRP profile. The structural stiffness of the four-span space truss decreases at the post-failure stage, and the large nonlinear deformation capability provides an early warning before the ultimate collapse. In addition, a finite element model considering material nonlinearity is developed to predict the failure mode, overall structural stiffness, and load-carrying capacity of the GFRP space truss structure.