Fracture diagrams of prismatic specimens with an improved contact stress distribution law

Abstract The authors have previously improved the principles of distribution contact normal and tangential stresses at moment destruction specimen on basis L. Prandtl’s method as applied to rocks. article presents further development for constructing out-of-limit curves “stress - longitudinal deformation” diagrams A comparative assessment proposed calculating in comparison with has been constructed by E.P.Unksov method. It found that parameters differ numerical values direction increasing reliability. Comparison calculated ordinate crack tip” – according E.P. Unksov testifies level current strength decreases two cracks small angles internal friction. allows determine ultimate residual rock samples using their shear strength, internal, friction coefficients, elastic modulus, which simple methods can be established experimentally laboratories mining enterprises. results used control state mass effective during disintegration.