Effect of intensity measures on the response of a 3D-structure under different ground motion duration

In seismic performance assessment of structures, the features of ground motion (GM) duration on the response of building structures remain vague and have inconclusive results. Also, intensity measures (IMs) link the ground motion hazard with the structural response; hence, using a suitable IM plays a significant role in the prediction of structural response. In this research, the effect of strong ground motion duration and the correlation coefficient of different intensity measures on the residual inter-story drift (RIDR) of a three-dimensional steel structure were investigated. Using nonlinear dynamic analyses and a total number of 34 earthquake records, the relationship between short- and long-duration seismic parameters including amplitude, energy, and frequency content parameters were investigated. The correlation between the 14 selected scalar intensity measures and the RIDR of the structure was also investigated. The results showed the highest correlation between the seismic parameters, such as Peak ground acceleration (PGA), Housner Intensity (HI), and Velocity spectrum intensity (VSI), with other seismic parameters in both short- and long-duration strong ground motions. Based on the maximum residual inter-story drift index, Mehanny and Cordova index (IMC), Bojórquez and Iervolino index (INP), and the geometric mean of Sa (Saave) intensity measures represented the least dispersion versus long-duration records. On the other hand, INP, Spectra acceleration at the period of T1 Sa(T1), and Saave intensity measures showed the least dispersion versus short-duration records.