True-Triaxial Testing

The heart of the Rock Fracture Dynamics Facility is a technologically advanced true-triaxial computer controlled rock deformation system with integral permeability measurement and geophysical imaging capability. For the first time, it is possible to carry out multi-axis thermo-mechanical, geophysical, and hydrological measurements essentially simultaneously on rock specimens ranging from hard rock such as granite to weak rocks undergoing deformation well into the post-failure regime of brittle rocks. The deformation system simulates engineering and geophysical problems to depths of over 4000m at temperatures up to 200C, with maximum loads able to induce fracture and failure in rocks while continuously monitoring changes to the physical properties of the samples. The use of 80mm cubical samples loaded between computer controlled servo-hydraulic rams, provides the high degree of operational flexibility that is needed for the range of instrumentation used in the research, including the monitoring of permeability, seismic velocity, resistivity and acoustic emission in 3D. This allows the growth of fractures to be controlled and monitored over a range of simulated earth-like conditions.

Related Publications

  • Nasseri, M.H.B, S.D. Goodfellow, and L. Lombos, R.P. Young (2014), 3-D Transport and acoustic properties of Fountainebleau sandstone during true-triaxial deformation experiments, International Journal of Rock Mechanics and Mining Sciences 69, 1-18.
  • Nasseri, M.H.B, S.D. Goodfellow, R.P. Young, Investigation of permeability anisotropy and polymodal fracture pattern development using a true-triaxial geophysical imaging cell, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Goodfellow, S.D., M.H.B. Nasseri, and R.P. Young, Evaluation of Wave Propagation Properties during a True-Triaxial Rock Fracture Experiment using Acoustic Emission Frequency Characteristics, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Tabari, M.G., S.D. Goodfellow, M.H.B. Nasseri, and R.P. Young, 3D Anisotropic Velocity Tomography of a Water Saturated Rock under True-Triaxial Stress in the Laboratory, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Young R.P., M.H.B. Nasseri, and L. Lombos, Imaging the effect of the intermediate principal stress on strength, deformation and transport properties of rock using seismic methods, Ture triaxial testing of rocks, CRC Press, Taylor & Francisco Group, Balkema, 2013, 167-179.