Abstract: A three-dimensional stress test was conducted at 8 points at -120, -220 and -320 m levels of Liguanji Iron mine, and rock cores with strain gauge obtained was implemented temperature calibration and confining pressure calibration test.The results indicate that each of the principal stresses is in compression stress, without tensile stress.The in-situ stress field of the iron mine is in horizontal tectonic stress, the value of maximum principal stresses range from 10.29 MPa to 22.16 MPa, and their orientation was about SE-NW, the value of vertical principal stresses are close to the weight of top strata in unit area.The value of maximum shear stress at each point are greater, which is more than 2 MPa.The results provide a reliable basis for mining stope proper redistribution, tunnel disposal and anchor support design.

Key words: In-situ stress, Stress relief method, Liguanji iron mine, Mining engineering