FIELD: physics.
SUBSTANCE: when testing material medium for compressibility and shearing, the true limiting stretching-compression state of a solid mass of the material medium at a depth h from the surface of half-space below dies of different shapes and hardness is determined from the relationship: 
for 
(structured medium); 
(kG/cm2) for 
(disturbed medium); where 
is the main normal compression pressure (kG/cm2); 
is the main negative tangential shearing stress (kG/cm2); 
is binding pressure of the medium (kG/cm2); 
is gravitational (natural) pressure of the structured medium (kG/cm2); 
is gravitational pressure of the medium with a disturbed structure (kG/cm2); Patm=1/033 (kG/cm2) is atmospheric pressure on the Earth's surface; 
(kG/cm2) is the current compression pressure in the solid mass; 
is the negative tangential stress in the solid mass of the medium (kG/cm2); 
(kG/cm3) is specific weight of the medium in a disturbed state; 
(kG/cm2) is average critical (breakdown) compression pressure for the medium, 
(kG/cm2), and tangential shearing stress in the medium under the die is taken as negative on value, wherein the true limiting stretching-compression state of the solid mass of the material medium based on data on compression-shearing tests for compression of its samples is determined from the relationships: 
(kG/cm2) for 
(structured medium); 
(kG/cm2) for 
(disturbed medium); where γstrh=patm=1.033 (kG/cm2), 
is the main negative tangential shearing stress in the compression-shearing device (kG/cm2), 
is the main normal compression pressure in the compression-shearing device (kG/cm2), and tangential shearing stress in the sample medium under the die of the compression device is taken as negative on value, and the true limiting state of the solid mass of the material medium based on data of mono-axial compression-stretching of the sample of the medium is determined from the relationships: 
for compression; 
for stretching, and tangential shearing stress in the sample is taken as positive on value during stretching and compression.
EFFECT: enabling determination of true limiting stretching-compression state of a solid mass of a material medium.
3 cl, 9 dwg
