STABILITY OF ANISOTROPIC ROCK MASSIF WITH TWO ADJISENT SQUARE CROSS-SECTION OPENINGS SYSTEM

Anisotropic massif enclosing a system of two square openings condition calculation results are presented. For comparison, the results of the massif stability with the opening systems of round and arched cross-sections are given. . Calculations are carried out in the framework of a three-dimensional model of the geomechanical state of the anisotropic for strength massif with a system of openings. The model assumes the stress eld and massif discontinuity areas construction in the vicinity of the mine openings. The stress eld is constructed by a boundary element method, which consists of the numerical solution of the boundary integral equation of the second exterior boundary value task of elasticity theory presented by Fredholm integral equation of the second kind , and on the basis of the received solution, as well as the application of the fundamental Kelvin's solution concerning the effect of an in nite medium of a force calculation of stresses at the points of the calculated area of the massif. Massif discontinuity areas construction is done by evaluating the massif strength at the calculated area points, located on the regular attenuation surfaces and based on the Mor - Kuznetsov strength theory criteria. The set of points at which these criteria are violated, form its zone of continuity violation. As indicators for assessing the opening impact on the surrounding massif continuity zone violation are taken, as well as disturbance factor and the massif instability area boundaries. On the acquired results basis the massif geomechanical state analysis is done, depending on the openings position to each other.