SUPPORT TECHNIQUE OF STEEL FIBER SHOTCRETE FOR SOFT ROCK TUNNEL AT GREAT DEPTH

To counter the general behaviors of soft rock at great depth, a new support technique of soft rock tunnel at great depth is suggested in this paper. Firstly change the recently used sequence of bolting and shotcreting and then mix h the standard concrete with a certain amount of steel fiber to improve the mechanical behavior of standard concrete so that the shotcrete can meet the needs of large deformation of soft rock. The numerical modelling is employed to compare the support schemes and a reasonable scheme is proposed. The support scheme is practiced successfully at the transport tunnel on the level -575m of the Coal Mine No.10 of Hebi Coal Mining Administration.