1. Instability of Geological Materials under Three-Dimensional Stress Conditions
Poul V. Lade
The goal of this project is to study the conditions for instability of geological materials and augment an existing constitutive model for prediction of sandstone behavior as it relates to prediction of borehole stability. The project involves a combined experimental and analytical research program to investigate the fundamental characteristics and conditions leading to development of shear bands under three-dimensional conditions and subsequent sand production in sandstone and other types of rock and concrete. This program is required to verify the 3D constitutive model for concrete and rock, to provide experimental data for predictions of shear
banding and to formulate failure conditions in such materials. The diagram shows the stress-paths for the triaxial compression tests to be performed to study yield and failure surfaces in artificial sandstone.