Experimental study of perforated yielding shear panel device for passive energy dissipation

This paper describes an investigation into a metallic energy dissipater designed for earthquake risk mitigation of civil structures. It is called the Perforated Yielding Shear Panel Device (PYSPD). It comprises of a thin perforated diaphragm plate welded inside a short length square hollow section. The device is to be connected in the lateral load resisting system of a structure with the diaphragm plate being in the plane of the building frame. It is a displacement-based device in which energy is dissipated through plastic shear deformation of its perforated diaphragm plate. The PYSPD is a modified version of the previously tested Yielding Shear Panel Device (YSPD). Perforations on the diaphragm plate alleviate demand on supporting elements which reduces undesirable local deformations near the connections. As a result more stable force-displacement hysteresis is obtained. Three patterns of perforations are studied. Finite element models confirm that diagonal tension field develops under shearing action but stress patterns are affected by perforations. Two plate slenderness and three perforation patterns combinations were tested experimentally. Under quasi-static condition, devices with certain plate slenderness produced stable and repeatable force-displacement hysteresis, and achieved large energy dissipation capability. Compared to un-perforated specimens, perforations reduce elastic stiffness and yield strength. Under design displacement it produced a stable hysteretic behavior and endured code requirements against low-cycle fatigue.