Performance Based Seismic Design And Collapse-resistant Fragility Analysis For Energy Dissipation Structures With Viscous Dampers

Meeting the requirements of no damage under frequent earthquake, repairable damages underbasic earthquake and no collapse under rare earthquake can basically guarantee the safety oflife, but property damage is often more than the social and the owners could afford. ThenPerformance-Based Seismic Design (PBSD) has become the mainstream direction of theseismic design in the21st century. This method predicts possible losses of structures beforethe earthquake, and sets seismic performance objectives based on owners, and finallyachieves former goals through the structural design.Viscous dampers will dissipate energy, and reduce main-structural vibrations,and alsomake sure that the structure itself and persons, equipments, decoration in the structure are allin safety and normal use environments, when they are installed in specific parts of thestructure. As an increasingly mature engineering vibration technology, energy dissipationtechnology provides a new way to achieve Performance-Based Seismic Design based on theenergy dissipation structure.Based on the studies of structures of viscous dampers, mechanical models, relationshipsbetween each parameter and damper’s energy dissipation capacity, and on the theories ofPerformance-Based Seismic, Performance-Based Seismic Design method has introduced todesign and evaluate performance of seismic structure. Energy dissipation structures withnonlinear viscous dampers is taken as an example and performance-based seismic designapproach is proposed based on the code for seismic design of building (GB50011-2010) andDesign and Construction Manual for Passively Controlled Buildings by Japan Society ofSeismic Isolation. The main parameters of dampers for each storey are determined throughperformance curve of the equivalent single-degree-of-freedom system of the original structure.Then, a single degree of freedom structure and a6-storey reinforced concrete frame withnonlinear viscous dampers are designed by this approach and nonlinear time history analysison this structure with and without dampers is also performed by SAP2000for verification.Finally,20ground motion records are chosen for increment dynamic analysis (IDA) on one ofthe transverse frames in this structure and collapse resistance capacity is evaluated by collapsemargin ratio (CMR). The results show that the seismic performance has been greatlyimproved and the performance objectives have been achieved. In addition, the collapseresistance capacity has also been improved effectively. But record-to-record variation isobvious in the results from IDA with different ground motion input. So it is still imperative tostudy for the seismic design methods for structure with energy dissipaters, selecting groundmotion records reasonably and analyzing the dynamic response reliably under severe earthquake in future.