Energy-Based Design Process for Passive Control Structures Considering Torsional Effect

The seismic performance of structures associated with dampers, called as passive vibration-controlled structures, depends considerably on the damper’s mechanical characteristics, which is expected to dissipate most of seismic energy by their nonlinear hysteretic behavior. Force-based design procedure presented in ASCE7, mostly referred for the design of structures with dampers, has limitations in quantifying the plastic deformation capacity required for dampers. Moreover, there is a lack of knowledge in formulation for torsional effect, which is potential by irregularities according to variations in damper characteristics and irregular arrangement of the dampers. Therefore, it inevitably requires repetitive analysis to verify the seismic performance in the design. In this research, a design method is proposed based on energy-based design approach to consider the torsional effect on passive control structures. The proposed method is the prediction of seismic response of structures, which is obtained throughout a large number of nonlinear analysis. The yield strength distribution of dampers through the height of structure was found be vital parameter for energy dissipation. Therefore, the optimum yield strength distribution of dampers is suggested to evenly distribute the accumulated plastic deformation ratio in torsional systems. Also, the yield deformation ratio between dampers and structural members is suggested in order to induce the most of damage concentrated to dampers at each floor. The analysis shows that by selecting the appropriate range of damper’s characteristics such as strength and stiffness, the response of structures can be controlled in accordance with design objectives.