Abstract:
Lateral and torsional coupling may lead to much larger boundary displacements in asymmetric-plane structures compared with the ones in symmetric-plane structures. And it is very effective to install dampers to reduce the boundary displacements in asymmetric-plane structures. In this paper, the viscous wall dampers which have effective energy dissipation capacity are used to control the torsional seismic responses of asymmetric-plane structures. Research the mechanism and the optimal configuration of the viscous wall dampers in order to control torsional seismic responses effectively. Firstly, transform the stiffness matrix to the mass center of the energy dissipation structure. Secondly, transform the damping matrix which is in the damping center after installed the viscous wall dampers to the mass center of the energy dissipation structure. Finally, the nonlinear motion control equation which considers the torsion effect and the additional damping position effect can be established. And the expression of the structural displacement ratio can be derived based on the structure response. And using the motion equation to investigate the influence rules of structural torsion effect, which caused by the position of damping center, the magnitude of damping force and damping parameter. The principle plane configuration of viscous wall dampers and the computing method of an optimal damping parameter can be proposed by combining the structural displacement ratio expression. Take an L-shape high-rise building as an example, the viscous wall damper configurations and the damping parameter choice are selected from the principles above. The nonlinear time history analysis is carried out at the most unfavorable direction for an energy dissipation system. The results show that the reasonable configuration of viscous wall dampers can not only effectively control torsional responses of an L-shape structure but also greatly reduce the maximum boundary displacement and structural displacement ratio. These researches provide basic principles and design methods for torsional responses control of asymmetric-plane structures using viscous wall dampers. And it is also provide a good reference for the energy dissipation design of asymmetric-plane structures.