Borehole Stability Analysis in Transversely Isotropic Rock Using Anisotropic Failure Criterion

This study demonstrates the importance of considering anisotropy in borehole stability of transversely isotropic rock. Both analytical and numerical methods are conducted in order to analyze the horizontal borehole stability in transversely isotropic rock. The data for transversely isotropic rock are based on laboratory experiments on shale. The boundary condition is assumed as in situ stress based on the stress ratio of Pohang, Korea. The critical plane approach is applied to describe the anisotropic Mohr-Coulomb failure criterion. A various scenarios with depth in transversely isotropic rock are considered in order to examine the borehole breakout.