Mechanical properties of composite bolt connections with sleeve

Tensile tests were carried out on glass fiber composite round head bolt connections with and without sleeves. The load-displacement curves and failure mode of specimens were obtained, and the performance of composite bolt connections was studied. Based on the Chang–Lessard criterion, the corresponding damage program was written considering the out-of-plane failure mode. The strength calculation and progressive damage analysis of composite laminate bolt connections were carried out based on ABAQUS. The results show that the UMAT damage subroutine can accurately predict the failure load and simulate the laminate failure mode. The introduction of the sleeves can improve the ultimate failure load of laminates. In this paper, the A-1 group (with sleeve) is increased by 21.5% compared with A-3 group (without sleeve), and the A-2 group (with sleeve) is increased by 13.1% compared with A-4 group (without sleeve). Increasing the interference can improve the laminate stiffness, but has little effect on the failure load.