Abstract
This paper discusses the practicability of a three-dimensional groundwater seepage analysis system that uses an extended finite element method (X-FEM). In the groundwater flow analysis for planning and construction of a rock oil tank or a geological disposal repository for radioactive waste, generating meshes in a complex three-dimensional region where numerous strata and underground facilities are modeled requires much time and labor. X-FEM greatly reduces the problem because it can handle material boundaries independent of analysis meshes. This paper proposes a new function for handling material boundaries using X-FEM, and presents the details of formulation. The validity of solutions is shown as compared with conventional methods by conducting numerical tests concerning thin strata such as faults that cause problems in the implementation of X-FEM. Meeting the needs of practical analyses is another objective of the tests. Finally, the direction and rationality of the entire system are described.
