Seismic ahead-prospecting method based on delayed blasting excitation in the tunnel face: A case study

Abstract

Advanced geological detection technology plays a crucial role in identifying adverse geological conditions along tunnel routes, providing early warnings for potential disasters such as water inrush, and ensuring construction safety. Among these technologies, the seismic wave method is widely used for predicting geological conditions in tunneling projects. However, traditional seismic wave approaches often rely on additional seismic source excitation, which disrupts construction activities and slows progress. To address these limitations, this paper proposes an innovative seismic wave ahead-prospecting method that utilizes the seismic waves generated by blasting at the tunnel face as the seismic source, thereby eliminating the need for separate seismic source excitation. This study proposes a delayed blast seismic source excitation method, which effectively avoids the disordered reception of the reflected waves and successfully extracts the effective reflected waves. Additionally, an observation system tailored for large-charge blasting in tunnels is designed, ensuring equipment safety and efficient data collection. Numerical simulation results demonstrate that blasting at the tunnel face serves as an effective seismic source for detecting geological anomalies, such as vertical interfaces. The research presents an innovative concept for rapidly constructing tunnels utilizing the drilling and blasting method.