SEGMENTED FRACTURING HORIZONTAL WELL COAL SEAM GAS EXTRACTION METHOD FOR BROKEN SOFT LOW-PERMEABILITY COAL SEAM ROOF OR FLOOR

Disclosed is a segmented fracturing horizontal well coal seam gas extraction method for a broken soft low-permeability coal seam roof or floor, the method comprising: determining the type of a horizontal well on the basis of exploration data and mine data; determining the position of the horizontal well on the basis of the exploration data and the mine data; on the basis of the exploration data and the mine data, determining a target layer position of a horizontal segment of the horizontal well in a coal seam roof or floor, and the vertical distance between the horizontal segment of the horizontal well and a coal seam top/bottom face; determining a layout azimuth of the horizontal segment of the horizontal well according to the direction of the minimum horizontal principal stress in a target mining area; completing drilling of a vertical well segment; performing geologic steering drilling of the horizontal segment of the horizontal well by means of an azimuth gamma geologic steering method, and adjusting a dr