Numerical investigations on a novel resilient energy dissipation damper for multi-level earthquakes

To efficiently enhance the seismic performance of structures under multi-level earthquakes, one type of novel resilient energy dissipation damper for multi-level earthquakes (REDD) is proposed in this paper, and the mechanical models suitable for the proposed damper are suggested. Such dampers could obtain triple yielding points by employing different energy dissipation units, exhibiting different states in different earthquake intensities. Numerical simulation investigation of seismic performance was carried out on nine REDD models in software of ABAQUS. The influence of different parameters, such as the width-to-thickness ratio (b/t) of shear steel plate, the buckling-restrained devices, section forms and area of yielding portions in round steel bars on the bearing capacity and hysteretic energy dissipation performance of dampers were studied. The results show that the dampers could possess stable energy dissipation behavior and effectively achieve graded yielding energy dissipation under multi-level earthquakes. And the first and second yielding points exhibit a negative correlation with b/t of the shear plate, while the significant influence of the buckling-restrained device, section form and area of the round steel bar on the tensile and compressive bearing capacities. Furthermore, recommending that the diameter difference between the buckling-restrained device and the round steel bar be 6 mm. This bolt connected damper could be easily replace the energy dissipation units, which greatly reduce the repair cost and highly enhance the post-earthquake recovery ability of structure systems.