Study on optimum layout of roadway in close coal seam

Abstract

In order to solve the problem of serious deformation and damage of surrounding rock under the complex stress environment of gob and residual coal pillar of overlying coal seam in China Coal Tashan Coal Mine, FLAC3D (Fast Lagrangian Analysis of Continua) numerical simulation is used to study the different excavation schemes of the return air chute in the near distance coal seam mining of Tashan Coal Mine, and finally determine to leave small coal pillar for excavation. Moreover, the correctness of the scheme is verified by monitoring the displacement changes of the roof and floor and the two sides of the roadway in the later stage. The results show that the failure depth of the roof of the 6-m or 8-m small coal pillar scheme is smaller than that of other schemes, and the roof is easier to maintain, which can effectively control the deformation and failure of the surrounding rock of the roadway. Considering the actual production problems such as air leakage in working face, an 8-m small coal pillar can be selected. The method of theoretical analysis, numerical simulation, and field measurement is feasible, which provides a reference for the engineering practice of roadway layout in close seam mining.