Cyclic Performance of Variable Grooved Gusset Plate Dampers in Cross-Braced Frames

Abstract

This study examines a novel damper designed for installation in cross-braced frames to enhance their cyclic performance, referred to as the Variable Grooved Gusset Plate Damper (VGGPD). The damper comprises a gusset plate with multiple slits arranged around the diagonal braces. The steel strips between the slits undergo significant plastic deformation under in-plane double curvature, ensuring high ductility and effective energy dissipation. The proposed damper is developed through cyclic testing and numerical analysis conducted on cross-braced frames equipped with the VGGPD. The study investigates two configurations of the damper, characterized by variable thickness and variable length, to prevent concentration of plastic deformation in a specific region. The damper plate is divided into four sections, assigning specific thicknesses or lengths to the upper and lower parts, and different specifications to the middle part. The experimental findings indicate that both damper configurations significantly improve the cyclic performance of cross-braced frames, ensuring adequate capacity to accommodate the required deformations. Furthermore, the results underscore the cyclic behavior characterized by stable hysteresis loop shapes and effective energy dissipation during repeated loading cycles. Notably, specimens utilizing the VGGPD system exhibited ductility factors reaching values as high as 8. The VGGPD system, in particular, is capable of achieving a relative drift of up to 5%, a value that matches the drift observed in special moment frames and surpasses that of special braced frames. Further validation through detailed finite element analysis in ABAQUS supported these findings, with strong agreement between the experimental and numerical results.