Gob-side entry retaining blasting method for top-breaking and bottom-cutting of huge thick roof

The invention discloses a blasting method for an upper-cut and lower-cut gob-side entry retaining of a huge thick roof. The blasting method comprises the steps of upper-cut blasting of a coal seam roof and lower-cut shaped charge blasting of the coal seam roof. The method has the beneficial effects that through open-off cut roof deep hole blasting forced caving and unmined coal seam overlying roof deep hole presplitting blasting, blasting damage is generated between an open-off cut coal seam overlying rock stratum and an overlying rock stratum behind an open-off cut and an overlying rock mass of the unmined coal seam, the overlying rock strata in front of and behind the open-off cut are fractured along with coal seam mining, and the coal seam is exploded. Meanwhile, it is guaranteed that a rock stratum in front of a cut can fall along a blasting damage area along with coal mining, roof falling is guaranteed, meanwhile, the crushing degree of other areas of a roof is reduced, through undercut rock stratum shap