Performance examination of steel fiber reinforced shotcrete in tunnel and its engineering application

According to the mechanical analysis of principle of steel fiber reinforced shotcrete structure, the applicability of steel fiber reinforced shotcrete in the tunnel of single-layer permanent lining is researched. The mechanics function mechanism of steel fiber reinforced concrete is analyzed firstly, and then the reasonable proportion, tension, resistance of compression, flexural strength, first-crack strength and index of flexural toughness of steel fiber reinforced shotcrete are completed by laboratory test. Moreover, combined with the typical spraying test in tunnel engineering, the measured data of stress in wall rock, spray stress of steel fiber concrete and level convergence in tunnel are analyzed. The spotting spraying experiment in tunnel shows that the tensile strength and toughness of the steel fiber reinforced shotcrete are higher than those of general one, the stress distribution is more homogeneous, the yield capacity is better, and the rebound of the steel fiber reinforced shotcrete is reduced. The results show that steel fiber reinforced shotcrete is perfect timbering material for single-layer permanent tunnel lining and it has wider application.