..., however, the essential mechanical issues lie in keeping the stability of gangway, and therefore an optimal design of gangway is most important to secure the stability of mine as well as its productivity. For the optimal design of gangway space, the rock mass classification method for mine has been adopted...

... by numerical analysis using FLAC through the examination of their mechanical behaviors. . This work allows minimizing the damage to the nature as well as the expense of construction since the volume of the ex- cavation of the ground can be reduced by the optimal design of slope angles. REFERENCE Bieniawski Z.T...

...Collapse of a tunnel in weak rock and the optimal design of the support system Effondrement d'un tunnel dans une roche de mauvaise qualite et conception optimale du soutenernent Verbruch eines Tunnels im schlechtem Gebirge und die optlrnale Gesta!tung des Ausbaues H.S.SHIN, K.C. HAN, C.SUNWOO...