ABSTRACT CMS9523072 PI: Kemeny, University of Arizona Coupling phenomena are extremely important in rocks and include mechanical, hydraulic, thermal, and chemical processes. In this study, crack-induced coupling mechanisms will be investigated with both experimental and modeling studies. The focus will be on investigation of how mechanical loading, thermal loading, and the chemistry of the fluid environment in the cracks influences the flow properties of the rock. Experimental emphasis will be placed on a series of coupled mechanical/flow triaxial tests in which both axial and lateral permeabilities are measured while samples are subjected to triaxial stresses up to and past peak stress. Laboratory tests will also involve thermal loading (both uniform and borehole heating) and tests to study crack growth under different fluid chemistries. Modeling will be focused on development of a finite element damage model. Fracture mechanics-based relationships will be developed between the coupling mechanisms, and will include crack interaction effects. These relationships will be implemented into a finite element model to predict coupled behavior under complex boundary conditions. In addition, a discrete crack boundary element model will be developed to study the capability of crack growth due to thermal loading and under different fluid chemistries (via subcritical crack extension), and the capability of calculating the permeability through a generated crack population will be added.
