Block shear failure of the gusset plate with a riveted joint

The shear failure of a block is critically limited in axially loaded tension members, typically characterised by rupture of the net tension plane combined with yielding of the gross shear plane, or vice versa. Depending on the length of connections, the governing mechanism may shift to shear rupture with a tension-yielding plane. During service conditions, a structure is frequently subjected to cyclic loading, which results in fatigue failure at a certain stress level below the material’s yield strength. In riveted joints, sharp-edged discontinuities around rivet holes induce significant stress concentrations, which in turn promote rapid crack initiation. Primarily, the fatigue failure is governed by crack propagation rather than initiation. This research adopts a fracture mechanics-based approach to study the characteristics of crack growth in a gusset connection. Numerical simulations were performed here to comprehend the behaviour of crack growth due to axially loaded gusset plates with riveted fasteners. Crack initiation is assumed at locations of maximum hot-spot stress, with initial cracks introduced normal to the principal stress direction at rivet holes. Paris' law was employed to evaluate the fatigue crack growth rates while considering residual stress effects, Stress Intensity Factors (SIF), and stress ratios. The Extended Finite Element Method (X-FEM) is employed to simulate crack propagation and estimate fatigue life in terms of the number of cycles required to reach critical crack length. The study provides insight into block shear failure behaviour of tension members with non-staggered holes, highlighting fatigue performance of riveted gusset plates and angles under cyclic loading.