Acoustic Emission (AE) Setup

  • One triaxial setup equipped for  AE measurements on intact or fractured rock specimens
  • Sleeve with radial and axial P&S- wave transmitter-receiver pairs and twelve one-component piezoceramic receivers for passive monitoring
  • Hardware and software for acquisition and interpretation

Applications

  • AE rate vs. stress and strain; for evaluation of AE rate vs. strain development and failure process and during re-mobilization of fractures during residual shear
  • Event localizationin 3D space – time; comparison with fracture pattern from 3D re-constructed image based on CT scan of plug after test
  • Source mechanism of fracture events; using moment tensor inversion to highlight tensile vs. shear fracturing
  • Micro seismic;  upscaling/evaluations of AE for field scale micro seismic monitoring applications
Acoustic Emission

Figure: NGI's sleeve for acoustic emission (left), and CT scan of plug with shear fracture generated around a horizontal borehole (middle) and corresponding event localization (right)