Method for preventing hard roof large-area abnormal pressure coming from fully mechanized caving face

The invention relates to a method for preventing hard roof large-area abnormal pressure coming from a fully mechanized caving face. The hard roof large-area abnormal pressure coming phenomenon often occurs on the fully mechanized caving face. Therefore, a plurality of rows of shot holes are punched inside roof rock mass inside an auxiliary crossheading or a caving face air way and/or a caving face machine way in the fully mechanized caving face at the same time. The depth of each shot hole is smaller than 35m, the diameter of each shot hole is 75mm, the distance between the first row of shot holes and the caving face is 150m, eleven shot holes are punched in each row, the serial numbers of the shot holes in each row is number one to eleven, wherein the explosives are loaded in the number 2 hole, the number 5 hole and the number 8 hole to conduct explosion, and peeping instruments are installed in the number 1 hole, the number 3 hole, the number 4 hole, the number 6 hole, the number 7 hole, the number 9 hole, the number 10 hole and the number 11 hole. The holes in the same row are distributed in a sector shape in the same plane. After the explosives are loaded, the holes in the first three rows are exploded in sequence, and the three holes in the fourth row are exploded at the same time. By the use of the method, the phenomenon that the roof of the caving face collapses after a coal cutter just passes through the roof of the caving face can not occur, the phenomenon that the roof in a large-area goaf does not collapse for a long time does not occur, the safety of the fully mechanized caving face is effectively ensured, and the method is widely applicable to fully mechanized caving faces of various coal mines.