Study On The Structure Characteristics And Technique Of Surrounding Rock Ckntrol With Large Mining Height

Fully mechanized high cutting, an important developmental direction for thick coal seam mining, has been widely popularization and application under the appropriate coal conditions in recent years. The production practice of the big mining height shows that the roof control, supporting design, the structure and movement rules of the overlying rock strata with the big mining height are different from the mining height of the ordinary fully mechanized mining. Generally speaking, the working resistance of powered support with the big mining height is greater than it of ordinary fully mechanized mining height. But in production practice, the design of the roof control with the big mining height stope has no unified methods now, as a result,a lot of large mining height support intensity is very stronger, but supporting effect is not ideal, its fundamental reason is lack of the basis of the roof control design and clear knowledge for the structure and movement rules of the overlying rock with the big mining height stope for specific conditions.The coal seam has an average thickness of 4.67 meters in xiegou coal mine of XishanJinXing energy company.LTD.Its mining technology is large mining height. This thesis researched structure the characteristics and movement rules of the overlaying strata under the different length of thelongwall, gave the mechanics characteristic in the process of the overburden strata movement by theoretical analysis and numerical simulation.Through the mine pressure observation, the paper researched the law of the rock pressure behavior with the big height mining.On this basis this paper researched the relations between the overlying strata structure and rock pressure behavior.the main conclusions are as follows:1. The key of the surrounding rock control with the big mining height is the rock stratum of the fracture zone;2. The reasonable width of the coal pillar in Xiegou coal is 15-21meters.3. The support working resistance of the island is greater than the ordinary working face;4. The estimation of the overburden rock structure with the big mining height is different from the ordinary fully mechanized mining.