METHOD FOR DETERMINING RESIDUAL STRENGTH OF ROCKS

摘要

FIELD: testing equipment.;SUBSTANCE: invention relates to physical and mechanical testing of rock and half-rock rocks that have a brittle nature of destruction, and can be used in engineering and geological surveys. According to the method, monolithic specimens are tested for tension and compression under various types of stress state, determination of indicators of tensile and shear strength and maximum stress, corresponding to the equality of maximum and residual strength in the cases of high pressure. They are determined as the mechanical properties of the indicators of residual strength for various types of stress state depending on the residual strength under uniaxial compression taking into account the ratio of the strength of the monolithic rock shear and tear and stress, corresponding to the equality of the maximum and residual strength in the cases of high pressure. Monolithic sample is compressed with two oppositely directed spherical indentors prior to its splitting, the average tensile stress is determined σ_t sample rupture, and the average compressive stress corresponding to the limiting shear resistance along the surface of the greater of the zones of destroyed rock near the indentors. As the mechanical properties there are determined the parameters of the bilinear approximation of the dependence of residual strength on the magnitude of the minimum principal stress, limit of residual strength under uniaxial compression, residual adhesion under bulk loading and angles of internal friction, which correspond to the various types of stress, according to the formula σ_R = σ_t, where σ_R is the limit of residual strength, σ_t is the average tensile stress.;EFFECT: invention can be used in case of the engineering geological surveys.;1 cl, 2 dwg, 2 tbl