Study On The Surrounding Rock Control Technology Of Gob-side Entry Retaining In1000m-Deep Mine At Sanhejian Coal Mine

Based on the geological condition of Sanhejian coal mine and by comprehensive using of theoretical analysis, numerical simulation and combined with the method of industrial test, studied on the features of mining pressure appearances at 1000m-deep mine gob-side entry retaining of Sanhejian coal mine, and then raised the parameters of roadway-in support, roadside support and strengthen support skills. Main results are as follows:1.The features of mining pressure appearances at 1000m-deep mine gob-side entry retaining:1)as depth increased, the deformations of gob-side entry retaining surrounding rock are increasing;2) as depth increased, the stress of gob-side entry retaining surrounding rock are increasing;3) as depth increased, the plastic zone range of gob-side entry retaining surrounding rock are increasing;4)the deformations velocity of surrounding rock, which is behind the working face, at deep coal mine gob-side entry retaining is much faster than that in shallow gob-side entry retaining, what’s more, the surrounding rock, which is behind the working face, of deep coal mine gob-side entry retaining need much more time to be stable than that in shallow gob-side entry retaining.2. The material, which is used to build the roadside packing body, is determined as high-water material, and then got the roadside support skills, which are decided by the features of roadside packing body built by high- water material. Based on this, by using theoretical analysis and numerical simulation methods, the parameters of roadside support was confirmed.3. The strengthen support parameters of 1000m-deep mine gob-side entry retaining are determined with numerical simulation, and on the basis of which, the reinforcement mechanism is analyzed: reinforcement structure composed of High-strength steel counter-pulled bolts and steel ladder beam can enhance free surface confining pressure of roadside support pressure effectively and the resistance to deformation.4. Roadside support mechanism of 1000m-deep mine gob-side entry retaining is analyzed to determine roadway- in support skills, roadway-in support parameters, the strengthen parameters of upon roadside support roof and single hydraulic props, which are behind the working face, are determined combined with numerical simulation method.The above results were applied successfully in the field test of 7136 working face at Sanhejian coal mine.