发明名称 METHOD FOR STRESS RELIEVING OF ROCK UNDER CRUMPING HAZARDS IN CHAMBER-PILLAR TYPE HEADINGS
摘要 A method of relieving ground in the circumstances creating the risk of tremors in excavation headings mined using a room-and-pillar mining system by means of shooting with the use of relieving holes which, at the same time, allows for larger webs, characterized in that in each new technological web a portion of blast-holes, preferably breaking-in holes, is used as relieving holes which are bored to be up to 20 percent longer and whose diameter allows for filling them with the amount of explosives which is two, maximum three times larger per unit of the hole's length in comparison with the remaining blast holes.<IMAGE>
申请公布号 PL158270(B1) 申请公布日期 1992.08.31
申请号 PL19880272052 申请日期 1988.04.22
申请人 发明人
分类号 E21C;E21C37/12;F42D3/04;(IPC1-7):E21C37/12 主分类号 E21C
代理机构 代理人
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