NER Autolab 3000

Triaxial (conventional)

E54-715

MIT_NER3000

This apparatus was acquired in 2015 and is currently installed on the 7th floor of MIT EAPS (Fig. 3). This triaxial testing machine uses silicon oil as confining medium and allows for simultaneous measurements of permeability, resistivity, acoustic velocities, and mechanical properties of rocks at reservoir conditions. The large sample size (10 cm diameter x 20 cm length) allows up to sixteen acoustic transducers to be attached to the exterior of the rock samples; each may be used in either active or passive modes. Four additional built-in acoustic sensors are located along the sample axis. Acoustic data are collected in continuous streaming mode at 250 Msample/s. The mean-lithostatic and pore-fluid pressures are independently controlled up to 120 MPa; axial loads up to 4.89 MN can also be applied. An external furnace produces temperatures of up to 120˚C. Tests of mechanical failure, joint reactivation, hydraulic transmissivity and permeability, and hydrofracturing can be performed. We can also measure changes in acoustic wave velocity, locate acoustic emissions, and analyze the moment tensors of the events. The NER 3000 apparatus supports a comprehensive suite of physical rock properties measurements as a function of stress and temperature. The system runs most standard rock mechanics test regimens, such as hydrostatic compression, pure shear, unconfined compression, confined compression, creep, and uniaxial strain. Each of these tests can be performed at pore pressures and temperatures representative of reservoir conditions. The apparatus is particularly suited for large samples including core drill sizes up to 4 inch diameter. Standard sample sizes are 4, 2, and 1.5" diameter. The system is also equipped with three pore pressure ports (one electrically isolated) and 16x4 pins electrical feedthroughs. Part of the feedthroughs are specifically designed for acoustic measurements. End plugs with built in piezo source and receivers P, S-wave) are available for measuring axial velocities.

Loading; Unloading; Heating; High Pressure; Hydrostatic Tests; Elasticity; Local Axial Strain; Local Radial Strain; Elastic Moduli; Yield Strength; Failure Strength; Strength; Creep; Stepping; Dynamic Tests; Hydraulic Fracturing; Reactive Flow; Pore Fluid Control; Permeability; Steady-State Permeability; Transient Permeability; Drained/Undrained Pore Fluid; Triaxial Stress/Strain; Differential Stress; Resistivity; Electrical Resistivity; Acoustic Velocity; Acoustic Events; P-Wave Velocity; S-Wave Velocity; Source Location