Geo-Underground Structure Monitoring using Acoustic Emission

• • Acoustic emission signals from two sensors were used to monitor damage locations in tunnel specimen

  • The tunnel lining was divided into multiple zones to identify the region where damage occurred

  • Machine learning-based classification was applied to estimate damage zones using a minimal sensor configuration

Rock Fracture Monitoring using Electrical Resistivity

• • The test is based on the background that electrical resistivity shows identical flow behavior with permeability

  • The influence of geometric bariables of rock joints on the resistivity was studied through lab test

  • Relationship between the clay content and the electrical resistivity was studied

Undrained Shear Strength Estimation using Shear Wave Velocity

• • Undrained shear strength is estimated using shear wave velocity measured by a penetrometer

  • Seismic signals are recorded, stacked, and analyzed to determine travel tiems via first arrival, peak-to-peak, or cross-correlation

  • Shear wave velocity profiles are calculated using the mean refracted ray path, modified interval, and refracted ray path method