Mechanism research of overlying strata activity with fully mechanized caving in thin bedrock with thick alluvium
Abstract：Based on the methods of numerical simulation, theoretical analysis, field measurement and so on, the break- age mechanism of overlying strata of uhrathin bedrock and thick coal seam and mining-induced development were studied. The results indicate that with the weathering, mechanical property of ultrathin bedrock substantially reduces, there are key overburden in coal roof, stress arch is in dynamical balance by mining, and apsidal angle is located in gangue of worked out section and coal wall in front of working face, underground pressure of working face is not obvi- ous with the influence of stress arch; stress arch prevents the growth of the fracture during mining, the growth of the fracture during mining depends on the final height of the stress arch, fracture grows quickly and closes easily, although the height is gigantic, valid water-guiding erack does not grow high finally. The research result properly explains the phenomenon of big static pressure, little dynamic pressure,little coefficient of live load, insufficieney of fracture grow- ing and so on under conditions of fully-meehanized top-coal caving mining with ultrathin bedrock and thick coal seam, made safe and efficient production come true under conditions of fully-mechanized top-coal caving mining with ultra- thin bedrock and thick coal seam.
Keywords：thick alluviumthin bedrockfully mechanized top coal caving miningmining fissuresstressed arches
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 1105-1110 )