The Research Of Thick Seam Fully Mechanized Mining The Overlying Strata Disaster Law

Recently, rockburst accident frequently occurs at some coal mines as the mining capacity and depth keep increasing, which seriously affects mine safety. Therefore, it is of great significance to reveal the mechanism by which intense strata pressure produces after the excavation of the coal seam, and employ effective action to weaken and control the strata pressure intensity.This thesis, which is based on Huating mine area with Yanbei coal mine being the research object, firstly demonstrated that the major influencing factors which result in overburden catastrophe are syncline structure, mining depth, mining method, pillar size and mining sequence after analysing the geology condition. Secondly the relationship between strata pressure in the stope and the movement of overburden failure was studied by conducting physical simulation experiments in the laboratory and numerical modelling. Th e results indicated that the combinatorial key stratum did not fail and did well in terms of controlling the overburden after the first mining face was excavated, while the combinatorial key stratum was fractured and great energy was released as its maximu m load bearing width was reached after the excavation of the second mining face. And when the third mining face was excavated structure instability of the combinatorial key stratum occurred, leading to intense rockburst. Then, by the means of the analysis of the experiment result, it was pointed out that reasonable mining face width, decreased pillar size and logic mining layout contributed to the staged release of the energy from structure failure of the overburden, eventually decrease the damage degree of the rockburst. The study also analysed the relationship among overburden movement and deformation law, formation of rockburst and the evolution of overburden structure by the use of strata control theory, indicating that the rockburst at Yanbei coal mine was result from the gravity of overburden and high crustal stress. Lastly, the study proposed the actions which include mining with a limited height, mining with narrow pillar or without pillar, reasonable mining sequence and layout, pressure-release-blast, coal seam water injection and pressure-release-drill to weaken the damage of overburden failure.