Study and Test on Development Regularity of Mining Speed of Coal Seam Separated from Overburden Strata

In the sedimentary coal stratum, rock stratum exhibits layered feature and has an obvious level. Overlying rock often produces separation along the level after the underground coal mining. But, due to the difference in the layers of rocks, the change of the mining process, the difference height in the level and other factors, the rule of separation is extremely complex. Therefore, in this paper, the allometric phenomenon, feature and laws of mining overburden separated strata are found by means of experiment and numerical simulation. The paper reveals the mechanical mechanism of allometric development of overburden separated strata, establishes its development formula based on the theory of beam in the mechanics, analyzing the space-time law of mining subsidence and overburden separation, and finally finds the relationship between surface subsidence and allometric growth of mining overburden separated strata, establishing the subsidence model based on allometric growth of mining overburden separated strata.