Analysis On Roof Stability And Research On Roof Behavior Characteristics In Thin Bedrock Working Face

There is high reserve of coal seam with thick surface soil and thin bedrock,such as Shendong coal field,Huainan-Huaibei and Henan mining area. In recent years,some coal mines have occurred several accidents as supports crushing and water inrushing when mining under such thin bedrock and caused economic loss and casualty,threat safety mining.According to the specific engineering geological conditions of1611(3) mining face,Further research on strata-pressure behavior at thin bedrock were studied totally by theoretical analysis,numerical simulation, field measurements etc. Meanwhile, research on support compatibility and roof control technology in such conditions. After the study,this dissertation draws conclusions as follow:(1) According to numerical simulation analysis of overlying strata failure law, coal mining lead to stress concentration region on both sides of working face and tress decreased region above goaf; vertical stress will decrease with the distance between strata and coal seam become increase,decreasing tendency will decrease gradually with the face length become increase.(2)Master the characteristics of the face based on field measurement;according to support resistance,mining height and condition of roadway deformation during face mining, obtained the ZY10800/30/65hydraulic support cannot afford safety and efficient mining requirement and analysis the reason of the support damage.(3)Analysis on causes of the four times roof leakage during face mining and forward specifical measures force on concrete conditions, which realizes the safe mining.The results provide important references and theoretical basises on the mining of safety and disaster prevention skills of support crushing and water inrush accident...