New conditional,scenario-based,and traditional peak ground velocity models for interface and intraslab subduction zone earthquakes

Abstract

The Pacific Earthquake Engineering Research (PEER) Center next-generation attenuation relationships for subduction zone earthquakes (NGA-Sub) ground motion database is used to develop new conditional ground motion models (CGMMs), several scenario-based ground motion models (GMMs), and a traditional GMM to estimate the peak ground velocity (PGV) for subduction zone (interface, intraslab) earthquakes. The PGV estimate in the CGMMs is conditioned on the rupture distance (R_rup), magnitude (M_w), time-averaged shear wave velocity in the top 30 m (V_s30) and pseudo-spectral acceleration PSA(T _PGV ). The period T _PGV in the CGMMs is magnitude dependent to account for the magnitude dependence of the earthquake source corner frequency in the Fourier amplitude spectrum. Several scenario-based models are developed by combining the CGMM with PSA GMMs to directly estimate PGV given an earthquake scenario and site condition. Scenario-based models capture the complex ground motion effects in the underlying PSA GMMs and ensure the consistency with a design PSA spectrum, which is desired in engineering practice. In addition, a traditional PGV GMM is developed using Bayesian hierarchical regression. Finally, we compare all of these models and find that the scenario-based models are consistent with the traditional model developed in this study giving confidence to their use. The conditional and traditional PGV GMMs developed in this study benefit the performance-based design of engineering systems affected by subduction earthquakes when PGV is an important intensity measure.