Stability analysis and support design of Glandroud coal mine tunnel

This paper reports the results of a research study which was carried out in order to analyze the stability of a tunnel at Glandroud coal mine, which is situated in northern Iran. The tunnel, with dimensions of 3 x 3.2 meters, was excavated at a depth of 150 meters below the surface. A numerical method was used to analyze the stability of the tunnel. Due to the structural features and geology of the area, the distinct element method was used and the code utilized according to this method was UDEC. The results obtained from the numerical analysis show that instability in the tunnel is due to block falls from the roof and sidewalls. In view of this, various support systems were analyzed. This analysis shows that a combination of grouted rock bolt and shotcrete is the most suitable support system in Glandroud coal mine tunnel.