METHOD TO PREPARE DIFFICULT-TO-CAVE PERMAFROST ZONE ROOF FOR INITIAL CAVING

摘要

FIELD: methods of underground mining, particularly to prepare permafrost roof rock for initial caving. ^ SUBSTANCE: method involves drilling belt entry and air way; cutting mounting chamber at excavation pillar boundary; installing mining complex and applying mechanical and thermal action to roof rock. As belt entries and air ways are cut slots are made in seam roof beginning from distance measured from excavation pillar boundary equal to expected initial caving increment. The slots extend for depth of not less than 1.5 m with slot plane inclination to horizontal plane of not less than 45°. After slot cutting hot air from local heaters is supplied into the slots. ^ EFFECT: decreased initial roof caving increment and increased safety along with equipment breakage elimination. ^ 3 dwg