Tectonic stress environment of coal-rock dynamic hazard in Kailuan mining area, China

Using HI (Hollow Inclusion) method, the in-situ stress of Kailuan mining area was measured in the field. The characteristics of the in-situ stress field and the relationship to regional structures are analysed systematically. Then the relationship between in-situ stress field coal-rock dynamic hazard, include coal and gas outburst, rockburst and water inrush, is analysed. Studies show that in-situ stress field in Kailuan mining area is a high stress zone of Earth dynamical field, with the horizontal tectonic stress being dominant. The magnitude and azimuth of the stress regime is controlled by Kaiping syncline. In-situ stress is the highest in Kaiping synclinal axis section, and as far away from the axis, the stress decreases gradually. The orientation of the maximum principal stress is approximate perpendicular to the axis of Kaiping syncline. The tectonic stress field also controls coal structure, gas content, coal permeability and other parameters. In the Kailuan mining area, coal and gas outburst and rock burst occurred in synclinal axis section of Kaiping syncline where in-situ stress is the highest, whilst water inrush occurred in the wing of Kaiping syncline where in-situ stress is the lowest. Coal-rock dynamic hazard in Kailuan mining area has almost identical tectonic stress environment.