Control Technology of Roof-Cutting and Pressure Relief for Roadway Excavation with Strong Mining Small Coal Pillar

In order to solve the problem of serious deformation and failure surrounding rock difficult maintenance gob-side entries with strong mining-induced small coal pillars, taking A110607 return airway Shanwenjiaba Coal Mine as engineering background, key parameters roof-cutting pressure relief control technology for roadway excavation pillars were studied by using two-way concentrated blasting technology, combined theoretical analysis, numerical simulation a field industrial test. A collaborative scheme “roof-cutting + anchor cable support” is proposed. The test results show that when height 8 m, angle 15°, width pillar 3 effect best. Through test, it was determined blast hole spacing 800 mm, 321 charge structure used in intact roof, 221 or 211 structures broken roof geological zones. During driving mining period, floor movement section reduced about 38% compared uncut section, two sides 44% section. It shows has good on mining.