The relation between mining pressure field-fracture field and gas emission of working face is analyzed, and the concept that there is a stress point (or strain point) among permeability of coal is presented. It is b...The relation between mining pressure field-fracture field and gas emission of working face is analyzed, and the concept that there is a stress point (or strain point) among permeability of coal is presented. It is believed that the mutation of coal permeability caused by the sudden loading or unloading of working face roof as periodic weighting occurs is the main reason that a lot of gas pour into the working face. Based on the above concept, the relation is established among abutment pressure during periodie weighting, permeability of coal seam and gas emission, and relation graph is drawn. Then the loading and unloading features of coal at the moment of fracture and non-fracture of main roof are revealed. And finally it is presented that the process of sudden loading or unloading as periodic weighting occurs plays an important role in rupture propagation of coal, analytical movement of gas and gas emission.展开更多
基金Natural Science Foundation of China (No.50974054)Doctoral Program Foundation of the Ministry of Education (No.20070460001)National Key Basic Research and Development Program (No.2012CB723103)
文摘The relation between mining pressure field-fracture field and gas emission of working face is analyzed, and the concept that there is a stress point (or strain point) among permeability of coal is presented. It is believed that the mutation of coal permeability caused by the sudden loading or unloading of working face roof as periodic weighting occurs is the main reason that a lot of gas pour into the working face. Based on the above concept, the relation is established among abutment pressure during periodie weighting, permeability of coal seam and gas emission, and relation graph is drawn. Then the loading and unloading features of coal at the moment of fracture and non-fracture of main roof are revealed. And finally it is presented that the process of sudden loading or unloading as periodic weighting occurs plays an important role in rupture propagation of coal, analytical movement of gas and gas emission.