Study On The Seismic Vulnerability Analysis Of Frame Structure

Earthquake is one of the natural disasters which exist in all over the world that cause disasters to the human world. With the rapid progress in urban development and the increase of population density, earthquake disasters will become increasingly serious. The economic losses and casualties which result from earthquakes are largely related to damage and collapse of buildings. Reinforced concrete framework is adopted extensively in metropolitan areas, therefore, it's with important practical meaning to analyze seismic vulnerability of the R/C frame.This paper through detailed analysis of the existing seismic structure models proposes a seismic damage index model with two variables. The main content of this paper is presented as following: First, several kinds of seismic damage index models are reviewed and their advantages and disadvantages are analyzed and compared; Second, this paper analyzes the characteristics of R/C frameworks. Previous studies and that of this paper indicate that remainder deformation and cumulative hysteretic dissipation energy are two important parameters which influence destroy extent of the R/C structures. Therefore, the paper establishes a seismic damage model with two variables. Two forms of formulae are used to describe the damage index: linear and non-linear forms; Third, based on the study on seven R/C frames under the ground motions from earthquakes of Tangshan,Haicheng and Ninghe earthquakes, IDARC₂D is utilized to perform the elastic-plastic seismic response analysis; Fourth, according to the damage state from the real earthquakes, this paper determines the real structure's damage index; Fifth, by comparing the calculated seismic damage indices with the real damage indices of structures, this paper uses the regression method to determine the model parameters; Lastly, through comparing the result by the two damage indices, we know that non-linear formula is better than linear one to describe the data.The research of this paper could become a reference for seismic evaluation and design of buildings.