FACTOR ANALYSIS-BASED GROUND MOTION FEATURE EXTRACTION AND THE MEASUREMENT OF THE POTENTIAL STRUCTURAL DAMAGE

The characteristics of earthquake intensity measures (IMs) were preferentially extracted by factor analysis through considering multiple IMs, and the principal factor of multivariate IMs in terms of a linear combination of the extracted fundamental factors was then constructed. The nonlinear responses of single degree of freedom (SDOF) systems modelled with different hysteretic models and multiple degree of freedom (MDOF) systems subjected to 2766 ground motions records were used. Nine IMs were selected and their characteristics were extracted by factor analysis and the correlation between the principal factor of multivariate IMs and damage measures (DMs) was investigated. The results show that the IM components belong to a stable principal factor irrespective of site category and the two principal factors extracted by factor analysis have positive interpretability. The site category, hysteretic behavior and lateral strength ratio have little influence on the correlation coefficient between the principal factor of multivariate IMs and DMs. The principal factor of multivariate IMs shows significantly high-level correlation with DMs through considering multiple IMs.