Cyclic Performance and Mechanical Characteristics of the Oval-shaped Damper

摘要

Every year earthquake damage causes hundreds of death all over the world. As much as possible, buildings should be kept in the elastic zone during an earthquake, therefore, the failure of building the main member is reduced. This paper investigated an oval steel shaped yielding damper used for seismic protection of chevron steel braced frames. The damper is designed to deform in-elastically under shear deformation to become energy dissipated. This oval steel shaped damper improves the braces buckling problem and reduces the required area cross section of chevron steel bracing members. To do this, eight models of the damper are proposed. For this purpose, finite element (FE) analysis with ABAQUS software is used to investigate and model the oval-shaped damper (OSD). The present study also investigated the damper strength parameters and seismic performance for applying to the steel braces frame. It is shown that the damper added between the chevron braces and the upper beam can reduce the lateral displacement and base frame force. Hence, the oval steel shaped damper is capable to absorb a great amount of energy with a stable hysteresis behavior. To do this, relationships are proposed and developed based on the maximum capability of the damper. The results show that this damper is responsible for absorbing input energy and increasing ductility frame coefficient. By comparing the analytical method and theoretical results, it is calculated that the proposed equations can be adapted to calculate seismic parameters like ultimate stress, ultimate shear force, plastic moment, elastic stiffness, stiffness degradation, deformation capacity, and resistance of the damper and calculate the exact location of plastic hinge. The structural designer, researchers and someone who like to develop the researches, it can be used and benefit for structural engineering.