Method for recovering jacking columns in distance by means of combined blasting of presplitting blast holes and radial blast holes

The invention discloses a method for recycling top columns in a distance-by-distance mode through combined blasting of presplitting blast holes and radial blast holes. The method comprises the following steps that (1) the length of the top columns recycled in a blocking mode is determined according to the width of the top columns; (2) digging a connection way from the pedestrian ventilation shaft in the stud to the footwall surrounding rock, and digging a top pillar blasting rock drilling roadway parallel to the top pillar at the end of the connection way; (3) top pillar presplitting holes and radial blast holes are dug in the top pillar blasting rock drilling roadway; and (4) firstly blasting the pre-splitting blast holes of the top pillar to generate pre-cracking cracks, then blasting the radial blast holes in blocks in a distance-by-distance manner to recover the top pillar, and after blasting, falling the upper-section waste rocks into the stope to fill the stope goaf. Compared with a traditional jack-pro