The Study Of The Overburden Breakage Character And Phenomona Of Ground Preaaure In The Great Mining Height Of The "Islated Island" Stope

The paper unifies the Huai Nan mining industry group XieQiao coal mine 1122(3) great mining height "isolated island" working face, studying the overburden breakage character and phenomona of ground preaaure in the great mining height of the "islated island"stope.According to the compound beam theory confirm the load on the rock stratum, analyze the condition destroyed that the rock stratum breaks. And make out the critical area of supercritical mining and get the corresponding calculation formula. And under the supercritical or non-supercritical mining ,gain two different kinds of the largest fracture height of overburden and fracture region shape. After exploitation the "isolated island"working face,the scope of goaf and critical area in double sides will from a whole. Wether the scope in double sides achieving or exceeding critical area will determine the breakage height of the overburden "isolated island"and the formative of breakage. We detail discussion of the overburden breakage height,the formative of breakage and the distribution of the abutment pressure of coal on the basis of it. The paper use FLAC to construct the mumeric model ,through the numeric simulation analyse and the actual observation to deal with the date ,and then I will get the feature of breakage and the disciplinarian of ground pressure in great mining height of "isolated island"stope on the overburden.The study of overburden movement law and phenomona of ground pressure of isolated island working face can be the base on road supporting and controlling effectly and preventing for calamity. It is enven the base on hight efficiency and safty extracting.