Constitutive Modeling of the Thermomechanical Behavior of Rock Salt
Abstract
For the safe disposal of heat-generating high-level radioactive waste in rock salt formations, highly reliable numerical simulations of the thermomechanical and hydraulic behavior of the host rock have to be performed. Today, the huge progress in computer technology has enabled experts to calculate large and detailed computer models of underground repositories. However, the big advances in computer technology are only beneficial when the applied material models and modeling procedures also meet very high demands. They result from the fact that the evaluation of the long-term integrity of the geological barrier requires an extrapolation of a highly nonlinear deformation behavior to up to 1 million years, while the underlying experimental investigations in the laboratory or in situ have a duration of only days, weeks or at most some years. Several advanced constitutive models were developed and continuously improved to describe the dependences of various deformation phenomena in rock salt on in-situ relevant boundary conditions: transient and steady-state creep, evolution of damage and dilatancy in the DRZ, failure, post-failure behavior, residual strength, damage and dilatancy reduction, and healing. In a joint project series between 2004 and 2016, fundamental features of the advanced models were investigated and compared in detail with benchmark calculations. The study included procedures for the determination of characteristic salt-type-specific model parameter values and for the performance of numerical calculations of underground structures. Based on the results of this work and on specific laboratory investigations, the rock mechanical modeling is currently developed further in a common research project of experts from Germany and the United States. In this presentation, an overview about the work and results of the project series is given and the current joint research project WEIMOS is introduced.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMMR51D..02H
- Keywords:
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- 0915 Downhole methods;
- EXPLORATION GEOPHYSICSDE: 3902 Creep and deformation;
- MINERAL PHYSICSDE: 5120 Plasticity;
- diffusion;
- and creep;
- PHYSICAL PROPERTIES OF ROCKSDE: 8168 Stresses: general;
- TECTONOPHYSICS