Assessment of Two Sets Intensity Measures of Ground Motion with Seismic Damage Indices of Masonry-infilled Steel Frames

The objective of this study is to investigate the nonlinear behavior of two dimensional 3, 5, 8 and 12 story steel frames with and without masonry infill considering the intensity measure (IMs) parameters of near-fault ground motions and dynamic Soil-Structure Interaction (SSI).A single story and single bay steel frame numerical model was validated by using two software, SAP2000 and OpenSees and comparing the structural periods obtained. Then the validation of OpenSees numerical model against the experimental results from literature was done. This was followed by using the validated models to create the rest of the numerical models. Aspect ratio of the superstructure and non-dimensional frequency are selected as the main parameters for the soil-structure system. Two sets of earthquake ground motions, ordinary seismic records (OSR) and pulse-like seismic records (PLSR) were used for the nonlinear dynamic analysis. Seismic performance was evaluated using the general indicators of damage (modified Park-Ang index), maximum inter-story drift ratio (MIDR) and roof drift ratio (RDR). The correlation between the multiple IMs with and without pulse-like seismic excitation and the damage indices of 3 forms of steel moment frames; bare, partially and fully infilled was determined using the Spearman correlation coefficient. Also, a significant part of correlation between the damage criteria and IMs was assessed. It was concluded that the spectral acceleration (Sa) and velocity (Sv) of the structures period strongly correlated with MIDR and RDR and that velocity correlated with the seismic parameters. The correlations for PLSR and OSR differed for each case and IMs with ground motion can help predict the parameters for building failure in various systems. In most ground motion parameters, the presence of masonry-infilled walls decreased the correlation coefficient for a fully infilled frame when compared to a bare frame. It should be noted that GSDI has high correlation with MIDR than with RDR. The correlation coefficients with the effect of the SSI were reduced by a range of about 10-20% for a model frame with flexible base when compared with the same model with a fixed base. Therefore, the use of PLSR is important when SSI is considered, since it generally negatively effects the correlation of damage indexes and causes considerable change in the behavior of partially infilled and fully infilled frames with respect to bare frames and high rise with respect to low rise frames. Keywords: Intensity measures, Ordinary records, Pulse-like records, Damage index, Steel frame with masonry infill, Soil-structure interaction