Numerical Study on Reasonable Entry Layout of Lower Seam in Multi-seam Mining

According to the geological conditions of 6# coal seam and 8# coal seam in Xieqiao Coal Mine, reasonable entry layout of lower seam in multi-seam mining has been studied by FLAC3D numerical simulation. Three ways of entry layout including alternate internal entry layout, alternate exterior entry layout and overlapping entry layout has been put forward for discussing on reasonable entry layout. Then stress distribution and displacement characteristics of surrounding rock have been analyzed in the three ways of entry layout by numerical simulation, leading to the conclusion that alternate internal entry layout pattern, which make the entry located in stress reduce zone and avoid the influence of abutment pressure of upper coal seam mining to a certain extent, is a better choice for multi-seam mining. The research results herein can offer beneficial reference for entry layout with similar geological conditions in multi-seam mining