A CAV Attenuation Model for Iran: Application to Liquefaction-Induced Lateral Spreading Assessment

A new attenuation model is proposed to estimate the cumulative absolute velocity (CAV) of strong ground motions based on an updated earth-quake database of the earthquakes occurred in Iran. The strong ground motion database is comprised from 4562 acceleration records of horizontal components associated with 574 earthquakes recorded in Iran during 1975-2019. A multiple regression procedure is used to develop the functional form of the predictive model as a function of the average soil shear wave velocity at the top 30 m (V-s30) of the recording stations, the moment magnitude (M-w), and the epicentral distance (R). Performance of the presented attenuation relationship is investigated by a parametric study and compared with some selected local-scale models recently proposed for CAV. Assessment of the model demonstrates that the magnitude-dependency of CAV is significant across all epicentral distances. The distance-dependency of CAV is particularly pronounced for M-w > 5.5. The influence of V-s30 becomes particularly prominent at extended epicentral distances exceeding similar to 50 km. The estimation of the liquefaction-induced lateral spreading is presented as an application of the proposed model for a typical site in Iran. The seismic sliding displacement is predicted similar to 31 cm, diminishing to similar to 2.5 cm when pore water pressure buildup is excluded from the calculations.