Study On Phenomenon Of Underground Pressure In Great-Inclined Coal Seam Mechanized Top Coal Caving

Taken Xinhe Colliery 3101 workface as the concrete condition, phenomenon law of underground pressure in great-inclined thick coal seam mechanized top coal caving is studied. Aimed at the geological mining condition Xinhe of Colliery 3101 workface, NO.3 coal seam and its roof & floor are tested for mechanical properties on MTS, and the real reliable mechanics parameters are obtained. Key questions and technology measure in great-inclined thick coal seam mechanized top coal caving is analyzed, and key technique of Xinhe Colliery mechanized top coal caving is studied. Through underground pressure observation of 3101 workface, the roof and top coal movement law is found out while great-inclined thick coal seam mechanized top coal caving, and the support's flexibility for roof movement and mining method is evaluation, which offers scientific basis for roof safety control and high production high efficiency. The generalized analysis indicates some laws. Because the upright pressure on support reduces but glide force increases when great-inclined thick coal seam mechanized top coal caving, guarantying support stability is the key for safety production. In order to avoid dropped roof to roll to t workface and be propitious to control roof, the workface should be false supine slanting arrangement. According to coal wall front force of support and workface support stress movement transformation relations, the main roof cycle pressure can be accurately forecast. Because the gangue glides down in goaf, the workface presents different underground pressure appearance; the sinking value of roof and support load is great in mid and upside but is smaller in downside. The practice proved that, mechanized top coal caving in great-inclined thick coal seam is feasible, and corresponding technical measure taken according to underground pressure law can realize seam benefit and seam safety with gently inclined coal seam. Those offered condition for later high production high efficiency in great-inclined thick coal seam.