Performance-based seismic retrofit design of existing building structures based on energy balance
Due to the increasing requirements in seismic design codes and the performance deterioration of structures during the long-term service,seismic performance of existing buildings will no longer meet the design requirements.It is imperative to conduct seismic retrofit design.However,the current retrofit design method usually needs a large number of repeated iterations of nonlinear dynamic calculation,increasing the design difficulty and reducing its applicability.A performance-based seismic retrofit design method is proposed for the existing buildings based on energy balance,which is applicable for structural retrofitting with energy dissipation devices.It considers the performance target of multiple seismic levels without nonlinear dynamic calculation and few iterations during the design.A benchmark steel frame is retrofitted by the proposed method,and nonlinear dynamic analysis is performed to evaluate the performance of the original and retrofitted structures.The results show that the drift ratio of all floors is significantly reduced after retrofitting,and the average decreases for service level earthquake(SLE),design basis earthquake(DBE)and the maximum considered earthquake(MCE)are about 20%,indicating that the seismic performance is significantly improved by retrofitting.The inter-story drift ratios of the retrofitted structure under SLE,DBE and MCE are consistent with the design values,illustrating that the expected inter-story and roof drift ratio targets are achieved,which verifies the effectiveness of the proposed method.The damper designed by the proposed method remains elastic state overall during frequent earthquakes,and enters yielding state during DBE and MCE,realizing the expected energy dissipation mechanism.The ductility demand of the damper is evenly distributed along the height,which further indicates the rationality of the design method.The presented research can provide important reference to the seismic retrofitting design of the existing building structures.
NETL
NSTL
万方数据
维普
