Mechanical behaviours of assembled hub joints subjected to axial loads

Abstract

ABSTRACT In this study, the mechanical performances of assembled hub (AH) joints under axial loads are investigated. Firstly, analytical solutions for the load-deformation characteristics of the AH joint system are proposed based on the rigid foundation-beam assumption. Axial tension and compression tests as well as finite element analysis are conducted to reveal the failure modes of AH joints with different design parameters. Moreover, a design method for AH joints is proposed to guide engineering applications. The type I AH joints exhibited three failure modes during the tension test: hub punching failure, hub fracture, and excessive deformation of the closure plate. Comparatively, the failure of joints was mainly caused by excessive hub deformation during the compression test. The initial stiffness and plastic capacity of the AH joints under two loading cases were identical. However, after entering the plastic phase, the tensile stiffness of the joints increased steadily, while the compressional stiffness declined with the plastic deformation. The type II AH joints exhibited brittle failure during the test. The initial stiffness and axial capacities obtained from the theoretical analysis agree strongly with the experimental results. The proposed theoretical formulae are useful for preliminary estimation of the mechanical performances of a new joint system.