Stress distribution and evolution characteristics in horizontal layered mining of steeply inclined coal seams

Abstract

In order to reveal the stress distribution and dynamic evolution characteristics of the surrounding rock under the conditions of horizontal layered mining of steeply inclined coal seams, the stress distribution and dynamic evolution characteristics of the alternate mining of two working faces at the same level were studied by using theoretical analysis and numerical simulation with B1+2 and B3+6 working faces in the south mining area of Wudong Coal Mine as the engineering background. The results show that: with the increase of mining depth, the overall peak pressure of coal body support in the two working faces increases and the peak point keeps moving downwards; the peak stress concentration in the coal body shows a “serration” fluctuation growth and the downward distance of the peak stress point shows a “step” growth. The B3+6 coal body stress peak is always greater than that of B1+2 coal body, and the stress peak position is always lower than that of B1+2 coal body; the linear correlation between the stress concentration peak and stress peak position and the mining depth of the two working faces is obtained by function fitting; the idea of impact ground pressure prevention and control scheme is proposed with the increase of mining depth.

Keywords

• steeply inclined coal seams
• rock burst
• horizontal layered mining
• mining depth
• stress evolution