Research on the Key Layers of Grouting Target for Overburden Abscission Layer in Lu'an Mining Area
The overburden abscission layer grouting is a systematic engineering,and its quality depends on the careful research and scientific operation of each link,among which the determination of key layers and grouting filling layer are key links. Through the implementation of multiple abscission layer grouting projects in the Lu'an mining area,it has been found that there are sometimes errors in the judgment of key layers in some mining areas,improper selection of grouting layers,and inadequate control of the grouting process. In order to reduce the blindness of project initiation and provide feasibility reference for abscission layer grouting,based on the study of some abscission layer grouting projects in the Lu'an mining area,it was determined that the grouting low position should be at least 25 times the coal thickness from the roof of coal seam 3,and the grouting high position should be taken as the larger of the depth of the bedrock weathering zone floor and 0.3 times the coal seam depth. It is analyzed that the key layer for grouting targets is generally sandstone or sandstone formations with a layer thickness of more than 6m. It mainly occurs in the Upper Shihezi Formation of the Paleozoic Permian,between the K10 and K12 sandstone in the key layer. According to the theory and engineering practice of abscission layer grouting,it is recommended to use single-layer abscission layer grouting filling technology for the mining faces located in zones Ⅰ and Ⅳ,and multi-layer abscission layer grouting filling technology for the mining faces located in zones Ⅱ,Ⅲ,and Ⅴ.
subsidence reduction in coal mining areasabscission layer groutinggrouting high and low layersLu'an mining area
万方数据
维普
