Research On Rockburst Monitoring And Prevention In Xing’an Mine Four Horizontal Switch Mining Place Of Working Face

Xing’an mine four horizontal layers1-3, Sec11North Face mining depth of600~680m,research shows that when the face mining depth over500m, rock burst occurred significantlyincrease the likelihood of danger. Because of the rise of deep coal and rock mass stress levels and nonlinearmechanical response, mine pressure response has been becoming increasingly serious and complicated, especiallythe increase of rock burst frequency and intensity, which is quite different with that of shallow mines. The study onrock burst prevention technology of deep working face is of great significance for safety mining of deep coalmines.Coal samples are taken from Xing’an mine four horizontal layers1-3, Sec11North Face, andare processed into standard coal samples. Then, the mechanical parameters of those samples aretested in the laboratory, the results of which showed small rock burst tendency.The characteristic of stress distribution in Xing’an mine four horizontal layers1-3, Sec11Northworking face of Shanzhai coal mine are analyzed though numerical simulation. The result shows thatthe upper section of the working face after curved mining has influence on the stress distribution ofthe corners in lower section. The stress distribution is more concentrated at the corners of curvedmining. As the distance between the working face and the corner reduces, peak stress of the upperoutlet gradually increases. However, the stress at the corner has not change significantly withworking face forwarding. When the distance reaches a certain limit, the peak stress gets its maximumvalue. While the working face is moving away from the corner, the upper outlet stress graduallyreduces.The micro seismic distribution law in curved mining process of Xing’an mine four horizontallayers1-3, Sec11North working face shows that in the early stage of mining, the sources are mainlyconcentrated in the front of the face along the return air roadway side. The day vibration energy andfrequency of micro seismic events are relatively small; As the distance between the Xing’an minefour horizontal layers1-3, Sec11North working face and the corner decreases, the sources aremainly distributed in front of the face, and the day vibration energy and frequency are relatively largewith fluctuation. After the working face surpasses the corner, the sources are mainly concentrated inthe middle front and rear of the face, and the day vibration energy and frequency gradually reducedas the face leaving away from the corner.The monitoring and rock burst prevention technical system near the curved mining of Xing’anmine four horizontal layers1-3, Sec11North working face is established, which includes the facemonitoring and rock burst prevention system. The practical effect of the site shows the technicalsystem brings better effect, which ensures the safe mining of Xing’an mine four horizontal layers1-3,Sec11North working face.