METHOD FOR STRENGTHENING OF ROCK MATTER Russian patent published in 1998 - IPC

FIELD: mining industry. SUBSTANCE: according to method, bore-holes are drilled over perimeter of underground working, water is injected into bore-holes, areas with intensive outflow of water to surface of underground working are noted, insulating coating is applied to noted areas, unstable cement slurry is injected twice into bore-hole by procedure which ensures constant flow rate until slurry starts flowing into underground working through narrow non-insulated fissures in its surface. Injection of unstable cement slurry into bore-hole is performed two times before outflow of slurry into underground working with strictly fixed value of flow rate of slurry injected into bore-hole. Application of method at first cement slurry injection cycle ensures sedimentation of cement particles at distance from mouths of fissures equal to bore-hole radius, and at second cement slurry injection cycle it ensures sedimentation of cement particles directly from mouths of fissures. Second injection cycle is started immediately after pressure drop in bore-hole. EFFECT: higher efficiency. 2 cl