Study On The Types Of Deep Clay-Weathered Rock Contact Zone And Disaster Mechanism Of Coal Mining

Water inrush, support crushing and other security incidents easily happen during coalmining near the deep soil-weathered rock contact zone. Currently, research is restricted to theunilateral nature of the soil or the weathered rock, it’s difficult to reflect the interaction and badengineering geology behavior of soil and rock. Therefore, research about types and engineeringgeological properties of deep soil-rock contact zone has important theoretical significance forsafe mining.Based on the composition, structural characteristics, water occurrence condition, deepsoil-rock contact zone types can be divided into sand-mudstone, sand-sandstone, clay-mudstoneand clay-sandstone. This thesis took Gubei coal mine in Huainan as a research object，there isonly clay-mudstone contact zone and clay-sandstone contact zone in Gubei coal mine. By highshear test, it got the basic shear strength parameters for clay-sandstone contact zone arec=0.24MPa, φ=7.68°, c=0.67MPa, φ=5.10°for clay-mudstone contact zone. UsingSEM(scanning electron microscopy) testing and MATLAB image processing method, this thesisanalyzed and quantitated the microstructure of the deep clay between shear zones. Deformationand failure characteristics of mining face were simulated using discrete element simulation,support crushing mechanism of thin bedrock roof in coal mining has been analyzed.Research findings have important basic application value for awareness and effectiveprevention of support crushing under soil-rock contanct zone in coal mining.