A method for evaluating earthquake-induced structural damage based on displacement and hysteretic energy

Abstract

Rather than viewing earthquake-induced structural damage as a single index of maximal deformation, it can be viewed as a combination of two indices, that is, the deformation demand and dissipation of energy. A method for evaluating the earthquake-induced damage of multi-storey buildings is presented that considers the maximal storey drift and the storey hysteretic energy. In this method, the maximal storey drift is estimated by means of the strength reduction factor spectrum, pushover analysis and distribution formula of deformation along structural storeys, which is based on the modal decomposition hypothesis in the nonlinear response stage of structures. For estimating the storey hysteretic energy demand, the normalized hysteretic energy spectrum of constant ductility factors is established, where the normalized hysteretic energy is defined as the ratio of the hysteretic energy to the square of the peak ground acceleration, and the formula for the distribution of hysteretic energy along structural storeys is derived based on the relation of the simplified internal forces of structures. For demonstrating the process of the proposed method and verifying its accuracy, an example is implemented, and the analysis results of the example indicate the following: (1) the method proposed in this article is a simple and easily implemented method for evaluating the structural damage induced by earthquakes and (2) the distribution formulas of the maximal drift and hysteretic energy along structural storeys derived in this article are relatively accurate.Keywords damage index, displacement demand, hysteretic energy, nonlinear response history analysis, pushover analysis, storey drift

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