Abstract：There are many kinds of in-situ stress measurement methods at present，which can be classified into mechanical，geophysical and geological structure information methods. Based on the analysis of the features of various stress measurement methods，a new method—hydraulic fracturing in-situ stress measurement with small borehole，which is suitable for rapid in-situ stress measurement in deep coal mine roadways，is introduced. The in-situ stress measurement principle，device and technical properties are introduced. Nine points of in-situ stress measurement have been completed in underground roadways in typical deep coal mining area，Xinwen coal mining area in China. There are 5 measurement points with buried depth more than 1 000 m，and the maximum is 1 220 m. The measurement results indicate that：(1) there are 7 measurement points with the maximum horizontal principal in-situ stress more than the vertical principal stress；(2) the value of the maximum horizontal principal stress amounts to 42.1 MPa；(3) the ratios of the maximum horizontal principal stresses to the vertical principal stress are 1.004–1.550；and (4) the in-situ stress field in Xinwen coal mining with buried depth more than 1 000 m is dominated by horizontal stress；and the orientations of the maximum horizontal principal stresses mainly concentrate on N3°E–N43.5°W. The in-situ stress states and the distribution law in the measured area have been determined through the measurement results. It is also proved that the hydraulic fracturing in-situ stress measurement with small borehole can provide an effective and rapid stress method for deep mines and can offere reliable basic parameters for roadway layout and support design.
