Studying On Deformation Features Of Surrounding Rock Of Large Sectional Roadway In Coalmines And Supporting Parameters

With the development of high yield and high efficiency and full-mechanized mining technology of modern mine, mining strength and scale of mine become high and large. In order to meet the need of ventilation, coal transportation and equipment installation, transportation and so on, roadway section becomes larger and larger. With the increment of roadway section, roadway maintenance becomes difficult, and it influences the production of mines. Supporting technique of large section roadway becomes a question that must be settled.This paper relying on nation technical project 'fast tunneling critical technique of large section with thick coal bed' (PN: 2006BAB16B02), supporting questions background of large sectional roadway with soft coal bed in ZHAOZHUANG Mine of JINCHENG Colliery Group, studied on surrounding rock broken laws of large sectional roadway and supporting technique with theoretical analysis, numerical simulation and test on spot, and put forward supporting designing of ZHAOZHUANG Mine.The chief achievement of this paper:(1) Analyzed the broken laws of roadway deformation and the influence factors of roadway stability, put forwards infinite thin plate mode of roadway roof. Based on the mode, this paper analyzed that with the increment of roadway width, the roof of roadway would deform and be broken by tensile stresses.(2) Through numerical simulation, this paper analyzed the influence of surrounding rock deformation, broken and stress distribution in different sectional sizes. The study indicated that with section of roadway increment, the degree stress concentration of surrounding rock and plastic areas would increase, the deformation of roadway would become worse, and the difficulty of roadway supporting would increase.(3) Analyzed argument adaptability and action law of cable supporting for large sectional roadway, put forwards high pre-stress, high strength rockbolt and anchor supporting way for large sectional roadway. For large span roadway, anchor supporting could decrease span of large sectional roadway; for high height coal roadway side, surrounding rock plastic area will increase sharply, surrounding deform sharply, high pre-stress anchor supporting must be used in two sides of roadway, and the length of anchor must be more than surrounding rock plastic areas. It should anchorage the shallow cracked surrounding rock in depth stability rock strata, which controlling deformation of sides and move along roof and floor.(4) On base of surrounding rock situation of large sectional roadway and deformation characters of ZHAOZHUANG Mine, with high pre-stress, one time anchor supporting theory, put forward roadway designing and application in filed. Mine pressure observation indicated that surrounding rock deformation of roadway has been relieved, and achieves prefect result.