Seismic Performance Assessment Of Reinforced Concrete Space Frames Based On 3D APA And IDA

Performance-based seismic evaluation (PBSE) requires exact and effect analysis methods to evaluate the seismic capacity of structures. Adaptive pushover analysis (APA) method and incremental dynamic analysis (IDA) approach are rational choices to run static and dynamic analysis for structures. However, 2D structural models are often adopted in performance-based seismic evaluation, which ignore the large difference between real 3D structures and 2D structural models. Therefore, it's necessary to carry out seismic evaluation employing 3D structural models. In this thesis, RC frame structures are taken as numerical cases to evaluate their seismic performance by the use of 3D structural models.According to the current Seismic Design Code Buildings (GB50011-2001) and Code for Design of Concrete Structures (GB50010-2002), three RC 3D frame structures are designed as case study examples. The software SeismoStruct is adopted as the analysis platform, and 3D time history analysis and 3D IDA are carried out in this platform under bi-direction excitations. 3D APA is run by acting the lateral forces in both x- and y- direction. The effects of lateral force mode on 3D pushover analysis result are studied by comparing the results with 3D time history analysis results. Based on the 3D IDA and APA curves, the capacity spectrum method (CSM) is improved to evaluate the seismic performance of 3D structures, with results compared with 3D time history analysis ones. It is illustrated by the comparison that CSM based on 3D APA and 3D IDA can exactly and efficiently evaluate the seismic performance of structures. Based on the analysis results, the 3D RC frame structures designed according to GB50011-2001 are safe enough under the designed seismic excitations.