Study On Surrounding Rock Control Of Old Mining Aera Roadway Excavation

The article according to No.3coal seam of the old mining residuesof Shanxi Jincheng Coal Co. Shenghua coal mine company as thebackground, research and analysis of the old mining area of secondaryroadway excavation surrounding rock control technology. According tothe site drilling roof sampling and lithology mechanical analysis andon-site field survey analysis, the status quo of the old mining area ofroadway, and the size of the old mining area roadway and other relevantparameters; the situation of secondary roadway excavation whencrossing; based engineering analogy bolting program selected differentsupporting program; supporting quality in different bolting solutionswhen secondary roadway excavation pass the empty lane, empty area,caving zone with numerical simulation software RFPA; Draw thefollowing conclusions：First, through the comparison with the old roadway in two roadwayexcavation entity in coal, coal excavation entity, damage degree of tunnelis less than the old mining area of roadway excavation through gob; theold mining area excavation without support of roadway crossing gob, gob caving zone roof damage increase local damage and even serious roof,roof separation, there are hidden dangers, the need for support;Second, The old mining area roadway crossing roadway, the factorsaffecting the magnitude of roof support effect in bolt strength, boltspacing, anchor length; supporting scheme selection of anchor strength of600MPa, the length of anchor bolt spacing is2m,600mm combinationsupporting scheme is the most reasonable, good control effect on the roof;Third, the old mining area roadway through the empty area, the sizeof the influence factors of roof support effect in strength, anchor boltlength, bolt spacing; old mining area roadway through the empty area,supporting scheme selection of anchor bolt length strength500MPa,2m,800mm from the anchor supporting scheme the most reasonable, goodcontrol effect on the roof；Finaly, the old mining area across the roadway caving zone, thefactors affecting the magnitude of roof support effect in bolt strength, boltlength, bolt spacing, but the length of anchor and anchor spacing on thesupporting effect is almost the same; old roadway crossing mining cavingzone, supporting scheme selection of anchor strength500MPa the anchorlength is2m,800mm, bolt spacing and supporting scheme combinationis the most reasonable, good control effect on the roof.