The Deformation Mechanism And Control Countermeasure Research Of Small Pillar Along Gob Area On First Mining Isolated Island Coal Face Of Jinyuan Mine

Small pillar technology to protect mine roadway becomes one of the important technical ways to enhancement mining area recovery coefficient by unceasingly development and consummation. The pillar dimensions are different, even the difference is very big, because of the differences of coal bed tax saves condition and mining engineering factor.The article in view of the No. 1321 isolated island working surface condition of Jinyuan Mine, analyzed the key aspects which influence the width of yield zone, derived the calculation formula of small coal pillar width, analyzed the surrounding rock stress and roadway deformation while the width of coal pillar is different by using the numerical simulation method, analyzed the change of surrounding rock stress before and after coal pillar excavating. The protecting roadway simulation of different width coal pillar indicated that, roadway deformation increased gradually along with the coal pillar width reduced gradually, especially when the coal pillar width reduced from 6m to 4m, the roadway deformation increased suddenly, showed the roadway stability drops suddenly.In view of the characteristics of small pillar to protect mine roadway in No. 1321 isolated island working surface and the problems needed to solve, the article put forward the concrete support design scheme through analyze the surrounding rock stress, and carried on the simulation to the supporting effect. The simulation result indicated that, the supporting had inhibitory effect to the roadway deformation, especially to the roof and the coal pillar side.Through the industrial test and analyzed the mineral pressure observation we can get that, the parameters of bolt and anchor cable is reasonable, the strength of coal pillar anchorage body is low, the width of coal pillar should be proper increased, the anchor supporting strength should be enhanced.