Correlation Analysis of Porosity and Uniaxial Compressive Strength of Jurassic Frozen Sandstone

To study the relationship between rock porosity and uniaxial compressive strength under freezing conditions, NMR and uniaxial compression tests were performed on Jurassic saturated aquifer sandstone under artificial freezing conditions. The relationship between temperature and uniaxial compressive strength and porosity under different temperature conditions was analyzed, and the porosity and uniaxial compressive strength were correlated. The results show that: the uniaxial compressive strength and temperature of sandstone satisfy the quadratic curve relationship; from -5 ℃ to -15 ℃, the increase value in uniaxial compressive strength decreases from 4.54 MPa to 0.54 MPa. The axial compressive strength growth rate decreased from 14.22% to 1.33%; the porosity of saturated frozen sandstone decreases with temperature, and its porosity also decreases, and the relationship between porosity and temperature complies with the power index function; the porosity of frozen sandstone and its uniaxial compressive strength meet the power index function relationship.