Mechanism and Application of Prestressed Yielding Support for Large-Span Roadway in Multistress Concentration Areas

Close-distance multilayer coal mining is common. Under the condition of extremely close-distance seams, it difficult to control surrounding rock large-span open-off cut roadways in multistress concentration areas. Based on engineering background 23616 roadway Chaili Coal Mine, this paper investigated influence upper close seam stress and deformation lower detail. The effect a high-strength prestressed yielding bolt cable was analyzed systematically. support system coordinated by member avoid excessive local structure reduce rock. Before after mining, changed mainly left right sides, displacement side roof. maximum roof at two observation sections 85 mm, 61 48 mm 68 53 46 respectively. relatively ideal, which can meet needs installation support.