Blasting vibration response and safety control of mountain tunnel

Tunnel blasting vibration will have adverse effects on adjacent existing villages. To ensure the normal life and safety of residents in these existing villages, it is particularly important to monitor and analyze the vibration induced by tunnel blasting. In this paper, with the blasting project of Chong-Li Tunnel under the existing village as an example, the characteristics of the tunnel blasting vibration response are analyzed. First, the blasting vibration velocity and frequency on the ground are obtained by field monitoring, and the propagation law of blasting vibration is studied. Second, a three-dimensional finite difference element model is established by numerical simulation and verified by the measured data. According to the numerical simulation results, the transverse influence range and longitudinal influence range of tunnel blasting vibration are divided, and the location of the measuring point with the largest blasting vibration response is determined. Then, taking the PPV with the largest vibration response as the control index, the corresponding control blasting distances in front of and behind the tunnel section are determined. Finally, 8 blasting tests with different charges per delay are carried out to obtain the control threshold of the maximum charge per delay.