The control and mine pressure of thick and strong roof stratum in fully mechanized caving mining face of high-gas thick coal seam

摘要

There are many high gas thick coal seams in our country. At present, gas pre-drainage meas ure is used to reduce gas on the face before the fully mechanized caving mine. Due to the limitation of mining condition, the threat of gas on the face has not been completely eradicated in the practical gas drainage. Meanwhile, because the thick and strong roof of high-gas thick coal seam in the fully mecha nized caving mining can not fall immediately with the process of mining, it will cause the gas to gather in the gob. When the roof collapses, it will cause tremendous pressure behavior which will endanger the safe ty of the mining. Concerning the problem of the rock burst of the thick and strong stratum, the paper re veals the relation between the broken movement of thick strong roof and surrounding rock pressure by ana lyzing the results of mining pressure of actual measurements of some fields. Furthermore, adopting the method of the water infusion to fracture and soften the roof before it collapses under proper circumstance will control the roof pressure effectively. By this way, on the one hand, it can control gas gathering space effectively; on the other hand, it can avoid the risk of the falling hard rock to burst and ignite the gas. The results of this study can provide reference for strata control and safe management in fully mechanized ca ving mining face of high-gas thick coal seam.