Abstract: In order to study the influence law of deep underground in-situ stress on the size of failure zone in surrounding rocks of mining roadway，an in-situ stress measurement was conducted under Yuncheng one kilometer-depth mine by means of hollow inclusion gauge method, and the in-situ stress state around the shaft station was obtained. Then the sizes of surrounding rocks’ failure zone in the walls of different roadways were measured with acoustic wave. The in-situ stress was transferred into initial radial stress and initial shearing stress on the vertical walls’ parallel sections. Through comparing the sizes of failure zones under different initial stress state, it was discovered that the influences of initial radial stress on failure zone in surrounding rocks were remarkable and the range of failure zones would be smaller with higher initial radial stress. Nevertheless, the influences of initial shearing stress were much less obvious. Besides, the measuring results also confirmed that the property of surrounding rocks and the size of roadway section were significant factors influencing the dimensions of failure zone.

Key words: in-situ stress, size of failure zone, initial radial stress, initial shearing stress