Simulation of soil liquefaction distribution in downtown Mashiki during 2016 Kumamoto earthquake using nonlinear site response

Abstract Several sites located between Road No.28 and Akitsu River in downtown Mashiki were liquefied during the mainshock of 2016 Kumamoto earthquake. According to building damage survey results, only a few buildings damaged areas proximate River, where liquefaction occurred, however, serious occurred neighboring regions. Therefore, effect soil on strong ground motions should be ascertained. Moreover, distribution visible invisible is required estimated as well. In this study, depth groundwater level was studied, which decreased from 14 0 m northeast southwest. Thereafter, nonlinearities shallow layers at four borehole drilling identified experimental data using Ramberg–Osgood relationship. Subsequently, dynamic nonlinear effective stress analysis one-dimensional column performed 592 seismological bedrock surface estimate mainshock. First, by corresponded observed Kik-net KMMH16. Second, nonlinearity considerably entire target area especially southern Mashiki, PGV similar after Furthermore, site whereas certain invisible-liquefaction north middle area.