Nonlinear analyses of soil amplification in the M_(JMA)8, 2003 Tokachi-Oki earthquake

摘要

Earthquake case histories of soil response over the last 70 years reveal the strongly non-linear hysteretic behaviour of soils. Over the years, numerous efforts have been made to represent more realistically soil response in the strongly nonlinear range. The paper studies three particular sites in the Hokkaido island during the M_(JMA)8.0, 26 September 2003 Tochachi-Oki earthquake. Borehole accelero-meters installed on the surface and the "bedrock" of these sites, provided a complete set of data. We subjected the profiles to the acceleration time histories recorded at their base. Numerical simulations are performed using research and commercially available codes: NL-DYAS, DEEPSOIL, ABAQUS, OPENSEES, incorporating several constitutive models. Numerical results for acceleration time histories and response spectra are systematically compared with those of the recorded motion.