Performance Based Seismic Design And Analysis For Energy Dissipation Structures With Nonlinear Viscous Dampers

The main purpose of Performance-Based Seismic Design (PBSD) is to make structure components to satisfy different function requirements in different seismic levels. Since 1990s, the study on PBSD had rised gradually in the United States, Japan and other developed countries, it represents the new development direction of the seismic design of engineering structures in the new century, and it has become the mainstream of the revise on the code for seismic sesign of buildings in each country in the 21st century.In addition, for 30 years with the development of structural vibration control theory, energy dissipation technology has gradually become an increasingly mature engineering vibration technology, it provides a new way to achieve Performance-Based Seismic Design based on the energy dissipation structure.Viscous damper is a typical kind of passive control devices, it is widely recognized in the civil engineering field, because it is not sensitive to the temperature and can keep the main structure in the linear stage within a broad frequency band besides other advantages. As a passive control device without needing external energy input, viscous damper absorbs and dissipates the most energy of the seismic input. Thus it can protect the safety of the main structure.Based on the relevant provisions on Performance-Based Seismic Design in Draft Code for Seismic Design of Buildings for approval which was issued in November 2009(Hereinafter referred to as " Draft Code for Seismic"), and the design method for structures with viscous dampers in Design and Construction Manual for Passively Controlled Buildings by Japan Society of Seismic Isolation, performance-based seismic design approach and analysis method for structures with viscous dampers are proposed. First, select performance target and determine the objective reduction ratio of displacement. Second, establish the performance curve for the equivalent single degree of freedom system of the main structure. Third, apply the loss stiffness ratio of the damper and the stiffness ratio of the equivalent supporting components to the main structure and determine the parameters of viscous dampers of each story.A 8-story reinforced concrete frame with nonlinear viscous dampers is analyzed by the proposed method. Simultaneously, time history analysis on this structure is also performed by SAP2000, the commercial finite element analysis software. Comparision indicates the proposed method is simple, straight-forward, and easy to perform. The results also show that the seismic action and structural response are obviously decreased after installing viscous dampers and the seismic performance objective is easily realized.