A Referenced Empirical Ground-Motion Model for Arias Intensity and Cumulative Absolute Velocity Based on the NGA-East Database

ABSTRACT In this study, we use the referenced empirical method of Atkinson (2008) to develop a ground-motion model (GMM) for estimating Arias intensity (IA) and cumulative absolute velocity (CAV) for the central and eastern North America. We use Campbell and Bozorgnia (2019) as the reference model. To achieve the objectives of this study, we begin with computing the geometric mean of the IA and CAV from the two as-recorded horizontal components of the motion for the recording motions in the Next Generation Attenuation-East strong-motion database. Then, we calculate the residuals of Campbell and Bozorgnia (2019) reference GMM for both IA and CAV. Next, we use the mixed-effect regression approach introduced by Abrahamson and Youngs (1992) to define adjustment factors to the Campbell and Bozorgnia (2019) model. Finally, we evaluate the proposed referenced empirical model by performing a set of residual analyses and comparing model predictions with observed data. The proposed model shows no apparent residual trend for magnitude or distance and implicitly accounts for the site term using the site factors proposed by Campbell and Bozorgnia (2019) model. The valid distance and magnitude range of the proposed model is the same as the selected reference model. In addition, we consider our new model to be applicable for time-averaged shear-wave velocity in the upper 30 m (VS30) between 150 and 2000 m/s.