The Research On Mechanical Characteristics Of Surrounding Rock And The Influence Of Interlayer Distance In The Process Of Protection Layer Mining

Mechanical characteristics of stope and Stress concentration characteristics of protected seam is researched comprehensively and systematically with different interlayer distance by using numerical simulation and equivalent material simulation and field measurement based on the mining condition and Engineering geological conditions of Xieqiao mine. The results show that: distressed zone which is at the upper part of the goaf is showed with the different face advance distance; the Stress concentration zone is surrounding the distressed zone. The stress concentration factor of surrounding rock is increase with Coal mining, but the stress concentration factor of surrounding rock reaches a steady state eventually; displacement field and damage field evolution constantly with coal mining; The stress concentration of protected is appeared in front of face and the back of open-off Cut, the width of stress concentration of protected seam is increased with interlayer distance increase, but the stress concentration factor of Protected Seam is decreased with interlayer distance increase.relationship is obtained between the stress concentration factor of Protected Seam and interlayer distance; relationship is obtained between the width of stress concentration of Protected Seam and interlayer distance.