Extended Simulation Research Articles

GMSS2.0: An Enhanced Software Program for Stochastic Finite-Fault Ground-Motion Simulation

AbstractThis article introduces an enhanced software program for stochastic ground-motion simulations using finite-fault sources, named Ground-Motion Simulation System version 2.0 (GMSS2.0). GMSS2.0 embodies an updated theoretical model of corner frequency and source duration, making the seismological model for defining the Fourier amplitude spectrum for each subfault more theoretically consistent. In addition, GMSS2.0 provides four rupture scaling relationships and five baseline correction techniques for end users to select the most suitable one for a specific application. For validation purposes, comprehensive comparisons between GMSS2.0 and EXtended SIMulation (EXSIM) for wide ranges of magnitude (M 4–8), distance (∼6–300 km) and spectral period (0.01–10 s) have been performed. The results show that GMSS2.0 can give remarkably close estimates to EXSIM with reasonable levels of accuracy. Finally, further validation is performed by comparing GMSS2.0 simulations with five Next Generation Attenuation-West2 ground-motion models for multiple scenario earthquakes with the updated site amplification for the generic California condition (VS30=500 m/s).

Stochastic Extended Simulation (EXSIM) of M<sub>w</sub> 7.0 Kumamoto-Shi earthquake on 15 April 2016 in the Southwest of Japan using the SCEC Broadband Platform (BBP)

Ground motions for Mw 7.0, 15 April 2016, Kumamoto-Shi earthquake of Japan are simulated employing Stochastic Extended Simulation (EXSIM) methodology within the Southern California Earthquake Centre (SCEC) Broadband Platform (BBP) version 15.3.0, utilizing the strong ground motion data from K-NET and KiK-net. Residuals [(ln(data/model)] are plotted as a function of hypocentral distance for a subset of eight periods. Trail simulations are run by varying stress drop until a better match of residuals is obtained. Validation exercise is run with a new data set to ascertain the accuracy of simulations. The results exhibit a close match between the recorded and predicted data. Adopting the validated seismological model of this study, ground motions are predicted at three important sites, which are devoid of strong-motion stations. These results can be used as inputs for conducting dynamic, response spectrum analysis of structures, liquefaction potential of soils, stability analysis and landslide runout estimation of slopes.