3. DESCRIPTION OF PROGRAM OR FUNCTION
UTAH-2 is a two-dimensional, thermomechanical finite-element program designed to analyze elastic, elastic-plastic, and elastic brittle response in anisotropic geologic media. Both constant strain triangles and quadrilateral elements composed of four constant strain triangles are used. The yield function for either elastic-plastic or elastic-brittle response is an extended von Mises criteria for geologic media with anisotropic strength properties. Additionally, the yield function considers the effects of confining pressure. UTAH-2 is able to consider temperature dependence of material properties. The elastic and plastic moduli as well as the thermal expansion coefficients can vary with temperature based on a polynomial fit of experimental data.
UTAH-2 is intended for use in analyzing stress and displacement fields associated with repository excavation, canister emplacement, salt over short time periods and in other geological media for any time scale; for evaluating room stability and generating boundary conditions (stress fields) used in canister sleeve studies; for analyzing bedded sedimentary regions; and for sensitivity and stability studies where temperature dependence of material properties may be a factor.