Method and apparatus for measuring initial stress in rock mass using low temperature thermal cracking phenomenon

摘要

And apparatus for initial stress measuring method in rock using a low temperature thermal cracking phenomenon is disclosed. After the formation of the borehole, it is possible to generate cracks in the borehole wall by applying a tensile stress to thereby cool the borehole wall, the initial stress measurement method of rock in using low temperature thermal cracking phenomena of the present invention, when the I measure the crack initiation point and temperature of. Thereafter, the temperature is measured of the opening time and thereby opening the crack is allowed to close the cracks generated and allowed to thaw the borehole wall, closed and allowed to cool again. calculating the initial stress of the rock using a second cracking temperature and cracking when the first cracking temperature at which cracking occurs is opened again. Cooling the borehole wall, re-cooling and de-ice, initial stress measurement device of bedrock in using low temperature thermal cracking phenomenon, to measure the crack initiation point and the second cracking temperature and the first cracking temperature.