Experimental testing and numerical parametric study of radially perforated plate damper in steel beam‑column connections

This study investigates the cyclic behavior of steel beam-to-column connections incorporating a radially perforated plate damper (RPPD). A single experimental specimen was conducted to assess the structural response of the proposed damper, which consists of concentric steel plates with radial slits designed to induce controlled in-plane plastic deformation. The specimen demonstrated stable, symmetric hysteresis behavior with no pinching or degradation up to a rotation angle of 0.08 radians. The test results showed a peak energy dissipation capacity of 15.37 kJ and a maximum equivalent viscous damping ratio of 0.171. The RPPD sustained 38 cycles under increasing amplitude loading and achieved a cumulative plastic deformation index of 331. Finite element analysis closely matched the experimental observations in terms of moment capacity, strain distribution, and failure patterns. A parametric study involving 24 specimens was then carried out to evaluate the influence of damper geometry on the system performance. Increasing the number of radial strips from 2 to 12 led to a threefold improvement in moment resistance and energy dissipation. Strip thickness and width were found to play a critical role, with a 1.5-fold increase in thickness improving energy absorption by 45% and moment resistance by 60% while doubling the width enhanced both by over 200%. Shorter strips yielded better performance, with a 30% improvement in the moment and energy metrics observed when length was reduced by 1.5 times. The findings support the use of the proposed system as replaceable fuses for seismic energy dissipation and provide detailed guidance for their geometric optimization in structural applications.