NESC9848 UTAH-2.

1. NAME OR DESIGNATION OF PROGRAM:  UTAH-2.

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.

4. METHOD OF SOLUTION:

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

UTAH2 is not appropriate for use in fully three-dimensional problems and cannot be used for long-term studies in salt where creep deformation becomes dominant. UTAH2 does not analyze creep behavior or take individual fractures into account.

6. TYPICAL RUNNING TIME:

NEA-DB ran the test cases included in this package on a CDC CYBER 830 computer. Execution times varied from 1.2 seconds (problem 3) to 223 seconds (problem 4).

7. UNUSUAL FEATURES OF THE PROGRAM

UTAH2 is intended for use in analyzing stress and displacement fields associated with repository  excavation, canister emplacement, and repository backfilling. It can be used to analyze deformation in salt over short time periods and in other geologic 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.

8. RELATED AND AUXILIARY PROGRAMS:

10. REFERENCES:

- INTERA Environmental Consultants Inc. :
  UTAH2: A Finite-Element Model for Simulating Thermoelastic-Plastic
  Behavior in Anisotropic Rock Masses
  ONWI-430 (April 1983)

11. MACHINE REQUIREMENTS:  46K words.

To run the test cases on a CDC CYBER 830, 140,100 (octal) words were required.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:

NOS 2.5.1 (CDC CYBER 830).

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHORS

           W.G. Pariseau
           University of Utah

           M. Golis
           Office of Nuclear Waste Isolation
           Battelle Project Management Division
           505 King Avenue
           Columbus, Ohio 43201

File name	File description	Records
NESC9848_01.001	Information file	52
NESC9848_01.002	JCL and control information	16
NESC9848_01.003	UTAH-2 FORTRAN source	2336
NESC9848_01.004	Sample problem input 1	260
NESC9848_01.005	Sample problem input 2	371
NESC9848_01.006	Sample problem input 3	65
NESC9848_01.007	Sample problem input 4	216
NESC9848_01.008	Sample problem output 1	307
NESC9848_01.009	Sample problem output 2	425
NESC9848_01.010	Sample problem output 3	116
NESC9848_01.011	Sample problem output 4	953