Tunnel-and-surface integrated seismic detection method based on passive and active sources

Tunnel boring machines (TBM) have gained extensive utilization in tunnel construction. Ensuring TBM construction safety hinges upon a precise understanding of adverse geological conditions. To predict geological conditions within the tunnel of the Hangzhou Second Water Diversion Project (Jiangnan Line), a geological analysis was conducted to estimate the potential adverse geological conditions ahead. To obtain the detailed distribution of fractured zones, we devised a tunnel-and-surface integrated seismic detection methodology. This approach integrates surface-wave detection, seismic imaging methods, Tunnel-Seismic-While-Drilling method (TSWD), and seismic ahead-prospecting methods. The surface-wave detection and seismic imaging method were initially employed to achieve a comprehensive assessment of adverse geology on a large scale. Subsequently the TSWD method and seismic ahead-prospecting method were applied within tunnel to get more accurate geological information. The integrated interpretation successfully identified five fractured zones, which were further validated through the analysis of TBM drilling parameters and measurements of uniaxial compressive strength. Compared to the preliminary investigation, the integrated detection method provided a more detailed insight into adverse geological conditions, thus enhancing the safety and efficiency of TBM drilling and tunnel construction. This study underscores the significance of accurate geological analysis for ensuring the success of TBM projects in challenging terrains.