Research On Collapse-resistant Capacity And Eonomic Loss Of RC Structures Under Strong Earthquake Based On Deformation

In the process of rapid economic development,there were a lot of existing buildings with different construction periods and different codes.How to evaluate the performance of such structures became a serious problem.Although performance-based design has been introduced in the current codes,it cannot be used in seismic performance evaluation directly beacause of the lack of relationship between components deformation and damage.Therefore,based on the latest research results about deformation limits of reinforced concrete(RC)components,this paper established the evaluation methods of seismic performance.In addition,based on accuracy verifications of finite element method,27 frame structures and 15 shear wall structures were designed as the research object of this thesis varying with height,seismic intensity and site characteristic period.The main research works and results of this thesis includes:(1)Research on the distribution law of the value of shear span ratio and bending shear ratio which were key parameters affecting the failure mode of components was carried out.As a result,the distribution law of the value of shear span ratio and bending shear ratio as well as failure modes of components in the structure are obtained.(2)According to the failure criterion of the first key component,the analysis about collapse-resistant capacity of frame structure and shear wall structure was implemented.As a result,The collapse probability of structures with different height,seismic intensity and site characteristic period under strong earthquake is obtained.It's found that the frame structure in the 7 degree zone and the shear wall structure designed with 0.65 s of site characteristic period in 8 degree zone had the worst collapse-resistant capability.(3)The comparison between the failure criterion of the first key component and interstory drift collapse criterion was conducted.And the conservative degree between two collapse criterions was obtained.Further analysis between component deformation and structural deformation was carried out,as a result,the interstory drift of frame structure when the first column was failure and the interstory drift of shear wall structure when the first shear wall and coupling beam was failure were put forward by regression analysis.(4)Seismic loss assessment based on deformation of components was put forward.Through economic losses analysis when structures sufferring rare earthquakes and extremely rare earthquakes,it is found that most of the frame structures achieved requirements of repairable structures under rare earthquakes,but less than 50% of frame structures were repairable under extremely rare earthquakes.The economic loss of frame structure in the 7 degree zone was more serious.For the shear wall structure,most of them were repairable in both of rare earthquakes and extremely rare earthquakes,but the economic losses in the 8 degree zone were more serious.