Abrasive water jet cutting methods for reducing blast-induced ground vibration in tunnel excavation

This study assessed the controlling effect of abrasive water jet cutting on blast-induced ground vibration during tunnel excavation. The abrasive water jet cutting method adopted in this study includes the notch-cutting and disc-cutting methods. The abrasive water jet notch-cutting method was applied to block the propagation of blast-induced ground vibration in the transverse direction of the tunnel face, and the disc-cutting method was applied to suppress the blast-induced ground vibration in the longitudinal direction of the tunnel. The vibration-reduction effects of both methods were quantitatively investigated through experimental and numerical studies. In the experimental study, the vibration-reduction effect of notch cutting was compared with that of the line-drilling method, whereas the vibration-reduction effect of the disc cutting was measured against the case without disc cutting. In the numerical study, the effects of notch slot length and disc slot diameter were investigated. The abrasive water jet cutting method reduced the blast-induced ground vibration and was more effective than conventional drilling and blasting method in tunnel excavation.