Feasibility analysis of excavation with open full section boring machine for ultra-long distance slant in coal mine

Slant is one of the development ways to guarantee the efficient production of mine. It can realize the continuous main transport of the mine, large mining – excavation – transport equipment can use trackless rubber-tyred vehicles directly reach underground, and without the complex ground disassembly and assembly in the underground large chamber. To meet the demand of 10.0 Mt /a production capacity of Kekegai Coal Mine in Shaanxi province, this paper analyzes the influence factors of mine access development mode and geological and hydrogeological conditions of Kekegai Coal Mine. Four kinds of mine development schemes are put forward. Considering the advantages of external transportation conditions, convenient site management, trackless rubber-tyred vehicle of slant with gentle slope and no need to change equipment, the development scheme of main and auxiliary slant + intake and return air shaft in Kekegai Coal Mine is preliminary determined. Through further reviewed the development status and trend of long-distance inclined shaft drilling and blasting tunneling and mechanical rock breaking tunneling technology in coal mine. The problems of low driving efficiency, excess working procedures and high risk in drilling and blasting method and cantilever roadheader construction in existing slant construction are analyzed. The technical scheme of using full section boring machine to drive super long slant is put forward, and applicability of open-type full section boring machine construction is demonstrated. By comparing and analyzing the advantages and disadvantages of the segment support and bolt-mesh-shotcrete support in slant, the supporting mode of bolt-mesh-shotcrete near working face and adding steel arch in the section with local broken surrounding rock is selected. According to the comprehensive analysis of engineering geology and hydrogeology conditions, environmental conditions, engineering conditions, mine construction technology, equipment performance, mine construction period, investment cost and other factors, the mine design and construction technology and equipment of main and auxiliary slant + inlet and return air shaft in Kekegai Coal Mine are feasible and advanced. It can provide a basis for the selection of the same type of mine development mode and the determination of the construction technology and equipment of ultra-long slant, and lay a foundation for the safe, efficient, green, and intelligent construction and development of coal mine.