Improving the Behavior of Reinforced Concrete Frame Using an Innovative Metallic Shear Damper

Abstract

ABSTRACTDespite the advantages of reinforced concrete (RC) frame, they are susceptible to damages under seismic loading. This is due to the fact that the main elements of the RC frame carry the gravity load in addition to the lateral loading. So imposed seismic energy is dissipated through the two ends of the beam, making the repair of the element complicated due to the gravity load. Although adding concentrically braced frames (CBFs) improves the lateral strength and stiffness, the ductility of the system is reduced. This shortcoming is due to the susceptibility of the diagonal elements to buckling. To do so, in this paper, an innovative metallic damper was investigated numerically and parametrically. The damper compound of the shear plate is surrounded by two HSS sections at two ends. The damper pertains to simplicity of construction and implementation. Also, the required equation to design and prediction of the system is presented. To investigate the behavior of the system, dynamic (to consider its suitable performance against seismic expiation) and static analyses (to determine the structural parameters) were carried out. Results revealed that the HSS section used as flanges for the shear plate not only improves the behavior of the plate but also contributes to resisting the applied load. Also, the reduction of the length to the height ratio of the damper enhances the stiffness and strength and stiffness. Subsequently, the variable Ф was defined as the ratio of the strength of the flanges to the web plate that affects the response of the damper. Although raising the Ф reduced the stiffness and ultimate strength, it is suggested to design dampers with Ф > 2 to achieve suitable overstrength in accordance with economical aspects. Also, time‐history analysis indicated that the proposed damper prevents the buckling of the CBF elements and improves the energy‐dissipating capacity of the system.