Numerical modeling of seismic waves by Discontinuous Spectral Element methods

09/2017

Numerical modeling of seismic waves by Discontinuous Spectral Element methods

Monday 20th February 2017

Antonietti, P.F.; Ferroni, A.; Mazzieri, I.; Paolucci, R.; Quarteroni, A.; Smerzini, C.; Stupazzini, M.

We present a comprehensive review of Discontinuous Galerkin Spectral Element (DGSE) methods on hybrid hexahedral/tetrahedral grids for the numerical modeling of the ground motion induced by large earthquakes. DGSE methods combine the flexibility of discontinuous Galerkin methods to patch together, through a domain decomposition paradigm, Spectral Element blocks where high-order polynomials are used for the space discretization coupled with a leap-frog time marching schemes. This approach allows local adaptivity on discretization parameters, thus improving the quality of the solution without affecting the computational costs. The theoretical properties of the semidis- crete formulation are also revised, including well-posedness, stability and error estimates. A discussion on the dissipation, dispersion and stability properties of the fully-discrete (in space and time) formulation is also presented. The capabilities of the present approach are demonstrated through a set on computations of realistic earthquake scenarios obtained using the code SPEED (http://speed.mox.polimi.it), an open-source code specifically designed for the numerical modeling of large-scale seismic events jointly developed at Politecnico di Milano by The Laboratory for Modeling and Scientific Computing MOX and by the Department of Civil and Environmental Engineering.