Experimental and numerical investigation of the effect of blast-induced vibration from adjacent tunnel on existing tunnel

Since the new tunnel is close to existing tunnel, the vibration wave induced by blasting endangers the safety and stabilization of the surrounding rock and the lining of existing tunnel. In the tunnel blasting vibration monitoring and safety prediction, Peak Particle Velocity (PPV) and vibration frequency are used widely as safety standards. To investigate the effect of blast-induced vibration from adjacent tunnel on existing tunnel, field monitoring experiments and a numerical method that is Finite Element Method (FEM) were adopted to study the blasting vibration velocity and vibration frequency of existing tunnel. Combined blasting vibration velocity with vibration frequency, the paper studied axial and radial blasting vibration velocity distributions and the corresponding Power Spectral Density (PSD) distributions of the existing tunnel under the effect of blast-induced vibration from adjacent subway tunnel. And the parameters of constitutive model and blasting loads were also discussed. It is shown that field monitoring experiment and numerical simulation can optimize blasting excavation program and provide a reference for other similar engineering projects.