Abstract
Since a region analyzed by the FEM must be finite, artificial boundaries are introduced into the model when a widely extending area such as infinite ground is analyzed. Special boundary conditions have been proposed for the artificial boundaries, such as a viscous boundary.
Although the commonly used viscous boundary has less ability to absorb energy, the boundary has many merits, for example, such as the applicability for nonlinear problem and simplicity of coding for computer programs. These merits are very important, especially for three dimensional nonlinear problems.
In this study, the viscous boundary for a full three dimensional interaction system was derived by virtual work. The effectiveness of the boundary was examined in detail, and it was found that the proposed viscous boundary showed good energy absorption, in contrast with previous formulation.
