Investigation of the interface phenomena due to interaction of high intensity stress waves with material boundaries. Final report, 1 November 1990-1 July 1993
A theoretical model for the interface between two geologically different rock layers, subjected to high intensity stress waves is developed in this research study The purpose for this model is to study the stress waves that are generated at the interface when there is large slip and failure along the interface. The stress range of interest was selected to lie above the elastic region, and below the region where the material behaves like a fluid (hydrodynamic region). This is due to a well understood behavior under elastic conditions, and the fact that in the hydrodynamic region the effects of the interface will be diffused. The model was developed by deriving appropriate stress-strain relationships, and solution of stress and displacement boundary equations at the interface. Because of the nonlinear behavior of geologic materials over the stress range of interest, and material failure at high stresses, the set of boundary equations at the interface was non-linear and discontinuous. This required the development of a numerical algorithm which was iterative in nature, and incremental in time. In each iteration the condition of failure at the interface and discontinuity of parameters across the interface were examined, and appropriate equations were selected. The results of the numerical modeling indicated that non-linearity in stresses and displacements, and material failure across the interface were important parameters in the generation of new waves at the interface. The generated waves included reflected and refracted P and S-waves, as well as surface waves that propagated along the interface.
- Research Organization:
- UTD, Inc., Newington, VA (United States)
- OSTI ID:
- 5371359
- Report Number(s):
- AD-A-272877/2/XAB; CNN: F49620-91-C-0008
- Country of Publication:
- United States
- Language:
- English
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