Studying On The Surrounding Rock Control Technology Of Roadway Under Extremely Loose Coal Seam

Our nation’s coal resources play a large amount in all energies. In the mining of coal, the deeper the mining depths grow, the more complicated the mining conditions as well as the roadway maintenance become, especially the support of roadway in extremely loose coal seam. The key of deep safe coal mining is weather we can solve the roadway support problems under this conditions.This paper studies on the surrounding rock control problem of roadway under extremely loose coal seam by the means of theoretical analysis, in-situ monitoring and numerical simulation, integrated with roadway excavation of II829working face at Huaibei Luling Coal mine.The main research contents of this paper are as follows:(1)Through the research of Luling Coalmine Project summaries, roadway summaries and gas control situations, proposing a scheme of roadway excavation.(2)Through analysis of the roadway destruction forms of Luling Coalmine, the reasons of frame destruction and the mechanisms of roadway destruction would be concluded.(3)By using the FLAC software to simulate and analyze three kinds of cross sections including rectangular section, vertical section and inclined semi-circular arched section, and by contrast of the stress field and displacement field of this three kinds of cross sections, we can confirm the cross section. Then we can conclude a proper support design when the support structure parameters and bearing capacity factors are analyzed.(4)The FLAC3D is used to simulate the variation of the stress field and displacement field of rock surrounding roadway on the process of the excavation, before and after the supporting stability, we can concluded that this support method effect well in extremely loose coal seam roadway.(5)By field experiment, mine pressure observation method, the rationality of the roadway support method and parameters, choused by the feedback field information, is validated.The main research content of this work provides theoretical reference to the surrounding rock controlling technology of roadway under extremely soft coal seam. Furthermore, this kind of support method has achieved good achievements on the support of extremely loose and roadway as well as technology and economy.