Range estimation of horizontal stress of deep rock based on Mohr-Coulomb criterion

Abstract

In-situ stress estimation is of great significance in deep coal mining. The vertical stress of the underground rock mass is generally estimated by the product of the upper cover average specific gravity and its depth, and it is difficult to estimate the horizontal stress. In this study, based on the Mohr-Coulomb criterion, the ultimate stable equilibrium conditions of the underground rock mass were applied to estimate the horizontal stress range. The estimated values agreed strongly with the in-situ measurement results, demonstrating the validity and feasibility of this estimation method. Meanwhile, this approach can explain the phenomenon whereby the ratio of the horizontal to vertical stress is distributed in a wide range of the shallow cruse zone but in a narrow range of the deep area. Furthermore, the influences of different parameters on the Mohr-Coulomb envelope were analyzed. Keywords: Rock mechanics, Horizontal stress, Mohr-Coulomb criterion, Deep rock