The research on underground pressure behavior of downward mining three soft thick coal seams based on analogous simulation experiment

摘要

In order to study underground pressure behavior of downward mining three soft thick coal seams, taking the situation of 5111B11b mining working face of Huainan mining group Xieyi Colliery as the research background and applying analogous simulation, movement characteristic of overlying strata and underground pressure behavior rule were obtained on the basis of physical and mechanical parameters of coal and rock samples from the colliery.In mining three soft thick coal seams, there was no significant change in the underground pressure behavior of the top layer coal seam mining compared with the single coal seam mining;In mining the bottom layer coal seam, the roof was very fragile, the phenomenon of piece of help and roof caving was very serious, underground pressure was larger, periodical underground pressure was not obvious and caving angle was larger than that of top layer coal seam.