| Performance-based seismic design theory has received wide attention by scholars from various countries since it has been proposed in the 1990s, and it has been carried out extensive studies. Unlike the traditional philosophy of seismic design which is only to ensure life safety, this theroy is committed to improve the seismic performance of structures. It can achive multiple performace objectives of building structures and require the design of structure has predictability under the earthquake that may occur in the future. Reinforced conctrete structure as the main structure of our architecture, studying its performance of various stages, from initial flexibility, and gradually degrade until the overall instability collapse, has impotant theoretical significance and practical value. Accordingly, under the supports of National Science Fund for Distinguished Young Scholars (No.50925828)《Structural health monitoring and vibration control》, by means of non-linear seismic response analysis, the performance-based seismic performance evaluation on reinforced concrete frame structures is done. The following main contents are studied through theoretical analysis, numerical simulation and some impotant results and conclusions have been achieved as follows:1. Taking 5-story,8-story,12-story and 20-story reinforced concrete (RC) frame structures as research objects and considering the random of structural parameters and ground motions, stochastic incremental dynamic analysis (IDA) under different damage measures (DM) is carried out to the four models. The results show that the IDA curves of each model have good convergence which proves that the choosing of intensity measures (IM) is effective. The stochastic incremental dynamic analysis provides the data support for the following performance-based seismic evaluation.2. Site hazard analysis and overall probability of seismic capacity analysis under different engineering demand parameters (EDP) are carried out on the four models. Site hazard curves and overall seismic hazard curves of different exceeding probabilities of each strcuture are obtained. The site hazard curves well reflect the hazard information of site design and thus provide ground motion parameters for engineering seismic design. The overall seismic hazard curves make the probablistic seismic capacity of the structure be unit time and extend the study area.3. Based on incremental dynamic analysis and seismic hazard analysis, seismic fragility analysis is implemented and fragility curves are received. When taking overall damage index of maximum drift represent structural response, based on Pushover analysis, the quantitative indexs under different damage states are found. When taking local damage index of curvature and steel stress of columns represent structural response, a method of getting the immediate occupation (10) and collapse prevention (CP) are proposed.4. The process of quantifying the seismic loss evaluation based on modified IDA has been introduced. A financial risk assessment methodology of building facilities under determined earthquake has been proposed, which can be mathematically represented as a quadruple integral. Using this method, the expected annual lossoes of the four models are calculated.5. Based on direct differentiation method (DDM), parameter sensitivity analysis is executed on RC frame structures, the effects of random parameters on the structural system are evaluated and the sensitivity of each parameter is obtained. Based on finite element reliability methods, the nonlinear static reliability analysis is carried out on the 5-story and 8-story RC frame structures. The reliability index and failure probability of overall deformation are gained. The results show that with the enhancement of seismic load, the reliability index reduces and the failure probability increases. There is little difference between the results calculated by different reliability analysis methods which indicate the correctness of the program. Based on finite element reliability theory MVFOSM, the overall seismic capacity of second-order moment statistical informations of each structure under different levels of earthquake are gotten, and are compared with the results of important sampleing. The analysis shows that the two methods'results are reasonable. Based on FORM and IS, the overall seismic fragility curves are acquired and they can provide reference for future seismic damage prediction.6. Based on orthogonal expansion method, the impact of time history response for the variability of structural parameters and ground motions are studied. The results show that the variations of mass and stiffmess have significant influence on the structural dynamic response, and the more number of random parameters the greater impact on the structural response. A synthetic random seismic model matching with target ground motion is introduced which can be directly used for performance-based seismic design. Keywords:performance based; incremental dynamic analysis; seimic hazard; seismic fragility; loss ratio;parameter sensitivity; finite element reliability...
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