Field Evaluation of Cable Bolts for Coal Mine Roof Support

摘要

Cable supports offer several advantages over traditional secondary supportmethods by enhancing stress redistribution to pillars and gob areas, minimizing or eliminating timbers and cribs that reduce ventilation, eradicating material-handling injuries related to placement of crib supports, and providing a cost-effective alternative to secondary support. The U.S. Bureau of Mines (USBM), researching alternatives to traditional roof support methods, designed and installed high-strength cable supports to improve the stability of longwall gate road and bleeder entries in a western U.S. coal mine. With the cooperation of industry, methods were developed to install cable supports in a tailgate and bleeder entry test area using traditional resin cartridges. Resin-grouted cable bolts were also installed and evaluated in additional longwall gate road and bleeder entry systems at the mine. The cable-bolted areas successfully maintained roof support throughout the tailgate and bleeder entries. Cable supports have replaced wood cribbing as secondary support in the bleeder entry system and minimized the use of cribbing in the longwall tailgate entries.