Analysis on site measurement of support pressure distribution law for seam of fully mechanized longwall top coal caving mining

According to the geological and technical conditions of the No.1151(3) fully mechanized longwall top coal caving mining face in Xieqiao Mine,the borehole stress meters were applied to measure the stresses in the coal pillars,mining seam and gateway side coal ribs during the mining process of the coal mining face.The research results showed that under the dissymmetrical mining condition,the stress distribution law in the seam of the coal mining face and surrounded round the mining gateway during the coal mining period were obviously different.There were support pressure peaks at the front area of coal pillars and coal mining face in strike direction.There was no pressure peak at the front of the coal pillars and in strike direct coal seam of mining gateway and the pressure peaks occurred at the rear part of the mining goaf.There were stress peaks both in coal pillars and the mining gateway's side coal seam in inclines direction.The stresses in the coal pillars near the coal mining face and the seam at the coal face were in a stress reducing area.