In this talk, I present some recent advances on seismic waves modeling in realistic media with elastoplastic behavior. After a brief introduction to the non-linear site response analysis in earthquake engineering, the capabilities of the discontinuous Galerkin finite element method (DG-FEM) are discussed in that framework. The method combines the geometrical flexibility of the finite element method, and the high parallelization potentiality and the capability for accurate simulations of non-linear wave phenomena of the finite volume technique. It has been successfully applied to elastic, visco-elastic and anisotropic media. The natural next step is to extend the method to elastoplastic soil rheologies found in the near subsurface. In our research group, we develop a discontinuous Galerkin method (nodal approach) for seismic waves in heterogeneous non-linear media. The method is based on high-order Lagrangian interpolation within the elements, upwind fluxes, and a fourth-order Runge-Kutta time scheme. The parallel Iwan model (Iwan, 1967) is used to account for the non-linear soil behavior, including hysteresis loops based on extended Masing rules. Comparison with different numerical methods shows satisfactory results for some canonical cases, for strains lower than 1%. Validation with real kik-Net data has been achieved within the Prenolin benchmark project.

References

Regnier J. et al (2016) PRENOLIN : International Benchmark on 1D Nonlinear Site‐Response Analysis—Verification Phase Based on Canonical Cases. Bulletin of the Seismological Society of America 106(5):2112-2135.