|
Increases the length of the face to mine high yield and efficiency focus on the production of another major technical direction , many mines in China are trying to increase the length of the face . Temple River , Shanxi Coal , the coal face length increased to 300m, with the increase of the length of the face , long face strata behavior law and the overburden Research into transport law become an urgent problem . In this paper, Temple East River coal mine four 4301 mining mechanized mining face as engineering background , using live rock pressure monitoring , theoretical analysis , means the combination of similar material simulation , numerical simulation , Temple River coal mine mining height , large buried 300m face deep strata behavior regularity of the overburden structure and dynamic characteristics were studied . Face Pressure behavior law analysis, the results show that the Temple River Mine face length increased to 300m , face to the weighting step short 225m face than ever , and the compressive strength is more relaxed , and found through on-site monitoring the 300m face ahead of the sphere of influence increases, the pressure was significantly lag mine ; support working resistance is mainly distributed in 6000 to 9000KN , and face along the dip direction the roof pressure was the middle , both ends , is greater than the characteristics of the nose and tail . Through the critical layer theory , similar simulation , numerical simulation method to analyze the roof structure , the analysis showed that the increase in the length of the face , roof fall height increase , 7.1m seam roof medium-grained sandstone control the rock into the range of caving zone , above the coal seam roof height of 22.93m range of caving zone , sink with a range of up 64.45m height range from caving zone with cracks , fissures bring the party into the bend .
|