Study On The Low Of Overlying Rock Destruction And Surface Subsidence By The Spontaneous Combustion Of Coal Seam

The spontaneous combustion of coal seam is one of five big disasters in coal mine. It results in a series problem of economy, environment and zoology, in this course, losing a large of coal resources, releasing a lot of poisonous and harmful air, destructive the surface and endangering safety production of mine and so on.However the study of the spontaneous combustion of coal seam causing surface subsidence deformation is very little, so the paper tries to study the problem. Starting with the course of coal heat convergency, by the thermodynamics, heat transfer theory and the convergency and dissipation heat model, analyses factors of the coal heat convergency and the separated strata fracture of overlying rock over gob, gives out single or more terrane movement character of rock bend subsidence. The influencing factor on the law of the overlying rock separated strata destruction is sorted two classes, the one is geologic condition including rock's hardness, interbed feature, hard large's existence and its position, existence form ofinsedimentary rock, geology structure ect. The other is mining technical conditions including mining method, the ratio of depth and thickness, obliquity of coal seam, size of mining dummy and mining speed and so on.Finally it studys the theroy of spontaneous combustion of coal seam combines with mining subsidence, and analyses the low of the overlying rock destruction and surface subsidence deformation, put forward the subarea and zone of overlying rock destruction by spontaneous combustion of coal seam. At same time, it compares the pace of mining with spontaneous combustion, thinks it is the one of primary factor of accelerating the surface subsidence.