In this study, subsequent to the collection and analysis of the tunnel design data in terms of each primary factor, and according to the classification considering each case, the FEM analysis is performed and the results are analyzed. After the appropriateness of the existing tunnel pattern is assessed, optimum supporting pattern is suggested.
The results obtained from this study are as follows: In the existing tunnel pattern, the tunnel crown has more stability than that of the side and lower half of the tunnel. Tunnel with shallow depth has also more stability than the tunnel with deep depth in the side and lower half. The result of the tunnel analysis and the failure model in publication have shown similar trend.
The thickness of shotcrete in the pattern traditionally used is suitable. However, it is estimated that the rock bolts are excessive in number and therefore, the modification in the pattern via the rock bolt number mediation is proposed.
In the tunnel design hereafter, if the pattern is selected and applied through the table which is suggested in this study, safe and economical tunnel design which corresponds to the real conditions of the tunnel will be feasible.