Thermomechanical effects

Abstract

Rock as a material cannot be characterized with great certainty. Heterogeneities, local anomalies, joints, fractures, and interbeds all introduce uncertainties in rock behavior. These uncertainties extend into models and mathematical idealizations of thermomechanical response of a rock system. The data base on site-specific rock properties and their dependence on temperature is just starting to emerge. The state of the art in thermomechanical modeling permits nonlinear behavior (e.g., creep), discrete discontinuities (e.g., joints, faults), and coupled effects (e.g., thermohydromechanical) to be included. Such models have not been adequately validated, although limited validation has been achieved for some aspects of thermomechanical response. In general, the ability to assign probabilities to the potential disruption of a repository system or one of its components as a direct or indirect result of thermomechanical effects needs to be developed. A careful repository design along with a reasonable factor of safety can significantly reduce uncertainties in the expected thermomechanical response in the preclosure and postclosure phases of a repository. -from Author