Assessment of Seismic Demands caused by 12 November 2017 Ezgeleh Earthquake (Mw=7.3) in Kermanshah

A severe earthquake ground motion with a moment magnitude of Mw=7.3 took place in the western part of Iran on 12 November 2017. The main objective of this study is to evaluate the seismic demands of structures under the recent November 12, 2017, Ezgeleh (Mw=7.3) earthquake. For this purpose, we selected the ground motions recorded at SarpoleZahab, Goorsefid, Kerend, and Javanrood stations that have maximum PGA. Evaluation is conducted by generalized interstory drift spectra, input energy spectra and ductility demands (μ) computed for selected records. Also, the time evolution of  the frequencyintensity content of selected records is discussed based on the Wavelet Transform (WT). Results showed that the (EW) components trigger larger interstory drift demands than those from the (NS) components. Particularly, it was identified that Sarpole Zahab and Goorsefid stations produced interstory drift demands significantly larger than those at other recording stations. Timefrequency analysis of groundmotions recorded at the Sarpole Zahab station shows that there is a transition of energy content of EW component with lower periods (i.e. 0.25 sec) to moderate periods (i.e.0.50,0.75 sec ) that it has a potential for moving resonance in buildings with short periods between (0.20.5 sec). Also, it can be observed that most energies of the NS component were highly concentrated at a long period band (between 0.9 and 1.5 sec) that is considered as pulselike. These findings are consistent with the damage observed in SarpoleZahab and its villages, where many dwellings and buildings collapsed or suffered severe damage during this event have a low fundamental period between )0.2 and 0.5 sec).