| Due to backward coal mining technology of Xinling coal mine early used, it left a large number of residual coal. In recent years, with the remaining reserves gradually less, coal production declined continuously, recovery of residual coal has become the main task of coal production. But because the original coal seam of residual coal repeated working face has been destroyed, there are lots of used roadways and coal pillars in working face, making mining conditions complicated, for example, the used roadways’ influence on roof stability, behavior law of mine pressure and coal rock stability and working face support and so on, these technical problems need to be solved.In this paper, based on the geological conditions of Xinling residual coal repeated working face, analysis working resistance of pillar and the stability of working face coal rock through theoretical analysis, similar simulation, numerical simulation and field test. To get the reasonable support resistance of pillar and the failure width of coal pillar through theoretical analysis. To analysis the failure law of coal rock and the behavior law of mine pressure through similar simulation. To analysis strata behaviors and the stability of coal rock with different caving ratio and used roadways spacing through udec. To analysis the distribution of lead abutment pressure, the movement law of top coal and the adaptability of single hydraulic prop.Research shows the reasonable working resistance of working face is 552 k N/m2, the failure width of coal pillar is 1.92 m, used roadways result in spalling and roof falling seriously. It can weaken strata behaviors and good for improving the stability of surrounding rock when caving ratio is 1:2. There are different coal rock failure characteristics under different used roadways spacing. The influence of lead abutment pressure is about 30 m, the peak is about 3.13 MPa, the main reason for the working resistance small is the roof above the working face falli. |
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