Projection Methods for Soil Structure Interaction Numerical Simulations with Non-Matching Meshes

MARCO SCHAUER; GUSTAVO A. RÍOS RODRIGUEZ

San Miguel de Tucumán

Congreso; MECOM 2018, XII Congreso Argentino de Mecánica Computacional; 2018

Univ. Nac. Tucumán, FACET y AMCA.

Nowadays, it is of great interest to perform numerical simulations of soil structure interaction (SSI) since they are applied to a wide range of engineering problems. These include the construction of reliable earthquake resistant structures in seismic active areas, or to increase the comfort of buildings by decoupling them from surrounding emissions like vibrations induced by traffic. To analyse SSI problems taking unbounded soil domains into account a numerical implementation of a coupled finite element method (FEM) and scaled boundary finite element method (SBFEM) approach is used in this work. This approach fulfills the Sommerfeld?s radiation condition. The FEM is used to discretise the so called near-field, i.e. the structure and its surrounding soil, while the infinite half-space or so called far-field is realised by the SBFEM. Both methods are coupled at a common interface, where specific information like nodal velocities and forces are required to be exchanged. Since computation of far-field solution demands more effort than for the near-field, it is desirable to use fewer elements in the far-field discretization than in the near-field. Therefore, a projection algorithm is needed to exchange information (i.e. nodal forces and velocities) at the interface between the non-matching meshes. A projection method borrowed fromthe fluid structure interaction framework is used in this work, namely the Nearest Neighbour projected method. It is wrapped in a library which is called during the coupled FEM-SBFEM solution process. A settlement SSI problem is considered to validate the implementation, as well as to evaluate the savings in memory and computation time. Matching mesh results are taken as reference.