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According to field investigation, roadway up-ribs coal body of sloping coal seam especially steep thick coal seam often appears unstable slipping phenomenon in the process of driving along coal roof, and lead to many security risks in field construction. Using synthesis research method, such as the field survey, laboratory tests, theoretical analysis, numerical modeling, and field industry application, the article preceded systematic study, combining on field engineering practice, to the roadway up-rib coal body unstable slipping mechanics and destabilizing feature of sloping coal seam along the coal roof driving. In response to the roadway adjacent stress characteristic and utilizing the basic principles of Bishop slice method, unstable slipping mechanical model of roadway up-rib coal body along coal roof driving was established, and then up-rib coal body stability safety factor was deduced, and analysis obtained that unstable slipping mechanics, destabilizing characteristic, and approximately position of unstable slipping region which was the up-rib coal body. Using distinct element software, it was analyzed the up-rib coal body slipping characteristic prior to roadway supporting, and put forward corresponding security protection measures in the process of roadway driving along coal roof. Based on the unstable slipping region of up-rib coal body, bolt supporting strength was determined, and through roadway bolt supporting numerical modeling in the case of varying coal seam slope angle, coal strength, roadway breadth and so on, appropriate bolt supporting parameters were fixed in different conditions. Research results were applied to practice and achieved good effects.
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