Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal sea...Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal seams and in front of excavated roadways. Survey devices, working methods and techniques as well as data processing and interpretation are discussed systematically. In addition, the direction of mini-wireframe emission electromagnetic wave of the full space transient electromagnetism technique was verified by an underground borehole for water detection and drainage. The result indicates that this technique can detect both horizontal and vertical development rules of abnormal water bodies to a certain depth below the floor of coal seams and can also detect the abnormal, low resistance water bodies within a certain distance of roofs. Furthermore, it can detect such abnormal bodies in ahead of the excavated roadway front. Limited by the underground environment, the full space transient electromagnetism technique can detect to a depth of only 120 m or so.展开更多
Statistics and analysis was made in causes, places and proportions about all kinds of disasters and accidents in coal mines of China in resent 50 years. The analysis indicates the emphasis reason that result in the ac...Statistics and analysis was made in causes, places and proportions about all kinds of disasters and accidents in coal mines of China in resent 50 years. The analysis indicates the emphasis reason that result in the accidents in coal mines are artificial cause explosion of mash gas and coal dust, water flood, fire hazard. The accidents mostly happened on stope which is more often than other places, following by the driving work face. This not only supplies the managers with basic reference about safe administration, but also suggests the countermeasures in reducing accidents： improve the disposition of person, perfect all kinds of rules and regulations, severely investigate, analyze and deal with the accidents.展开更多
文摘Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal seams and in front of excavated roadways. Survey devices, working methods and techniques as well as data processing and interpretation are discussed systematically. In addition, the direction of mini-wireframe emission electromagnetic wave of the full space transient electromagnetism technique was verified by an underground borehole for water detection and drainage. The result indicates that this technique can detect both horizontal and vertical development rules of abnormal water bodies to a certain depth below the floor of coal seams and can also detect the abnormal, low resistance water bodies within a certain distance of roofs. Furthermore, it can detect such abnormal bodies in ahead of the excavated roadway front. Limited by the underground environment, the full space transient electromagnetism technique can detect to a depth of only 120 m or so.
文摘Statistics and analysis was made in causes, places and proportions about all kinds of disasters and accidents in coal mines of China in resent 50 years. The analysis indicates the emphasis reason that result in the accidents in coal mines are artificial cause explosion of mash gas and coal dust, water flood, fire hazard. The accidents mostly happened on stope which is more often than other places, following by the driving work face. This not only supplies the managers with basic reference about safe administration, but also suggests the countermeasures in reducing accidents： improve the disposition of person, perfect all kinds of rules and regulations, severely investigate, analyze and deal with the accidents.
