Experimental and theoretical analysis of novel shear - Flexural combined metallic damper

Abstract

Energy devices are generally installed to improve the structural energy dissipation capacity and damping with the aim of absorbing the input energy and decreasing the damage of the parent structure. One of the most widely employed energy devices is metallic damper. This paper proposed a novel shear - flexural combined (SFC) metallic damper, in which the shear plate was clamped by the flexural plates on both sides to engender the interactive work between them. One pure shear and four SFC dampers were prefabricated with the identical nominal yield strength. Different shear - flexural thickness ratios (ts/tf) and spaces of flexural plates (s) were applied for the tested specimens. Cyclic tests were then performed to reveal their hysteretic performance and mechanical behavior. Strain distributions of shear and flexural plates indicated that the flexural plate provided satisfactory constraints for the shear plate to form local buckling between the adjacent two flexural plates in the post buckling stage. A high ts/tf might lead torsional failure of flexural plates due to the contact force induced by the buckled part of shear plate. More importantly, a modified force - displacement model was proposed to predict the mechanical behavior of SFC dampers. The buckling strength of shear plate was discussed to make the modified model coincide well with the experimental data. The experimental and analytical results confirmed that the proposed SFC damper had superior seismic performance and was suitable to be employed in building structures in earthquake regions.