Unsaturated Triaxial System

VJ Tech’s Unsaturated Triaxial System is used for triaxial testing in unsaturated (or partially saturated) soils. The Double Wall Triaxial Cell design ensures precision in measuring soil volume changes throughout the testing procedure by separating the acrylic Inner from the Outer Cells.

The Unsaturated Triaxial System is equipped with air bleed screws on both cells for efficient de-airing. The system features 6 valves for air/water control and can withstand confining pressures up to 2000 kPa. Base Pedestals, including those with encapsulated Bender Elements, feature an interchangeable ceramic disc (HAED) with the ability to separate the air and the water phases up to a specified air pressure. Top caps bring, also, an HAED allowing a double water drainage and reducing the testing time by 4 times (compared to single drainage). The Cell base incorporates 5 exit ports, accommodating On-Sample Transducers, Bender Elements, or a Mid-Pore Pressure Transducer for accurate geotechnical data.

Suction is controlled inside the sample through the axis translation technique, utilising a hydraulic and a pneumatic Automatic Pressure Controllers (APC) to impose pore air and pore water pressures. Sample volume changes are determined through a Volume-Change device and confining pressure is applied using a hydraulic APC.

csUNSAT software allows the automated control of all pressures and stresses when a test is performed. Available stages include Equalisation, Consolidation, Stress Paths (q – p – suction), Shear.