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| Category | Method | Distance (m) | Analysis of the characteristics of groundwater detection | Advantage |
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| Geological analysis method | Geological analysis of tunnel face | — | According to the situation of the tunnel face, the water outlet location and flow rate are recorded | Accurate observation of the location and volume of the effluent |
| Advanced drilling | 10–20 | To judge whether there is a water-bearing body in front of the tunnel face by observing whether the borehole is out of water and determining the amount of water flowing out of it | Accurate observation of the water output and water pressure |
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| Seismic wave method | Tunnel seismic prediction (TSP) | 100–150 | In the reflection layer, the shear wave velocity (Vs) tends to decrease, the ratio of longitudinal wave velocity to shear wave velocity (Vs/Vp) increases, or Poisson's ratio suddenly increases | Accurate recognition and location of anomalous geological bodies in front of the tunnel face (such as faults, underground rivers, and caves) |
| Tunnel reflection tomography (TRT) | 100–150 | Properties, size, and 3D holographic imaging of faults, fractured zones, karst caves, underground rivers, and other anomalous geological bodies in front of the tunnel face |
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| Electromagnetic method | Ground penetrating radar (GPR) | 15–30 | Frequency of electromagnetic wave decreases, resulting in multiple strong reflection interfaces, scattering, and diffraction, resulting in cluttered reflection waveforms | Sensitive to fracture zone, lithology, and water-bearing state changes |
| Transient electromagnetic method (TEM) | 50–80 | The resistivity of surrounding rock is obviously lower than that of surrounding rock | Sensitive to low resistor fracture zones filled with water |
| Other methods | Infrared water detection method | 20–30 | The detection instrument shows that the curve has a sudden change | Sensitive to water-bearing rock |
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