Cyclic response of mid-splicing replaceable links: A numerical study on bearing capacity and overstrength

• Validated finite element model (FEM) accurately predicts cyclic behavior and failure modes of mid-splicing replaceable links. • Link length ratio, bolt hole pattern, and flange splice plate design dominantly influence seismic performance. • Slotted holes reduce stress concentration and enhance overstrength coefficients. • Bilateral flange splice plates improve stiffness and energy dissipation compared to unilateral designs. • Vertical web bolt arrangements compromise bearing capacity and should be avoided. This study presents a validated finite element (FE) model of a mid-splicing replaceable link developed in Abaqus, calibrated against experimental data to ensure accuracy. The FE model's predicted hysteresis behavior, backbone curves, and failure mechanisms exhibited close agreement with experimental results, confirming its reliability for simulating seismic performance. Using the validated model, a comprehensive parametric analysis was conducted to assess the influence of critical design variables—including link length ratio, bolt hole geometry, flange splice plate thickness and layout, web bolt hole arrangement, bolt friction coefficient, and bolt grade—on seismic performance indicators such as overstrength coefficient, bearing capacity, and elastic stiffness. The results indicate that all specimens exhibit substantial plastic deformation capacity, with plastic rotations exceeding 0.08 rad. Both bearing capacity and stiffness are inversely proportional to the length ratio, decreasing progressively as the length ratio increases. Excessively small length ratios impair ductility and significantly reduce energy dissipation capacity. Additionally, the web bolt holes configuration plays a critical role in governing bolt slip behavior. Notably, specimens with vertically arranged holes exhibit the poorest performance due to restricted bolt slip, resulting in substantial degradation of structural performance. The thickness and arrangement of flange splice plates also significantly influence link behavior: excessive thickness impedes plastic deformation development, while insufficient thickness may lead to premature failure. Conversely, the bolt friction coefficient and grade have relatively modest impacts on the overstrength coefficients and bearing capacity. Notably, all configurations exhibited overstrength coefficients greater than 1.5, validating the robustness of the proposed replaceable link design for seismic applications. These findings provide critical insights for optimizing replaceable links in earthquake-resistant steel structures.