Research On Mechanism Of Sand Load Transmitting In Shallow Seam

With the implementation of the Western Development Strategy, ShenDong Mining Field, with numbers of hundred billion ton coal resources, has been an important base of energy production and has extensive international market.The mining practice of ShenDong Mining Field indicates: considerable cracks formed by violent ground behavior and ground subsidence make the serious loss of ground surface water resources, so it enlarge the desert, which influence and restrain the full development of modern high production and effective mine seriously.The core of ground control theory in shallow seam is roof structure and its stability. In traditional ground control theory, the load of key stratum structure is considered as static load because roof stratum of common work face is composed of many key strata. Provided that, roof structure' s stability analysis of ShenDong Mining Field is built on the static relation , there will be much different from the engineer practice. Practice demonstrates the load of key stratum in shallow seam exits transmitting effects and bears dynamic character.Based on the investigation of ground surface subsidence and deformation situation caused by shallow seam mining in Daliuta mine, etc of ShenDong Mining Field and the surveying of ground behavior of shallow seam long wall full mechanical mining workface, the practice character of sand dynamic transmitting of shallow seam is set up. In the theory guidance of key stratum of ground control and model of "short block structure of voussoir beam" and "step voussoir beam" , sand dynamic load transmitting test model is constructed and intellectual dynamic data acquisition instrument is explored. Through field simulation model test, the sand failure character of shallow seam during the first weighting, periodic weighting and full mining period is exposed and the law of sand to the key block in "step voussoir beam" dynamic load transmitting is presented primarily. Though numerical calculation method, the phenomena and resultsare testified.It has important theory meaning of this research to analyze the mechanism of sliding instability , study the relation of "support -rock" and establish dynamic roof structure theory.