Triaxial Test 2

This is an electro-pneumatic system with closed-loop digital servo control. An electro-hydraulic option is also available to perform tests at higher frequencies or amplitudes. This system is capable of performing fully automated static and dynamic triaxial tests on saturated and unsaturated soil specimens. The cell pressure, pore air pressure, pore water pressure/back pressure, and the axial loader are servo controlled. It is possible to control over 20 parameters (i.e. stresses, strain, suction, etc.) for real time display and/or control during a test. The graphical interface of this system is very useful for operating the equipment with minimal error. Some of the special features of this equipment are listed below.

• Fully integrated system with multi-directional automatic valves, volume change and diffused air flushing devices, de-airing tank, and vacuum pump
• Direct control/measurement of pore water pressure (u_w) and pore air pressure (u_a).
• Performs static and dynamic tests (Sat/Unsat Triaxial Shear with stress/strain path, Hydraulic Conductivity Measurements with suction control, Resilient Modulus, Cyclic Strength, etc.)
• Frequencies up to 5 Hertz (higher with electro­hydraulic option)
• Closed-loop digital servo control
• Double cell wall construction for accurate volume change measurements
• Easily exchangeable high air entry valve (HAEV) ceramic stones
• Complete “turn-key” systems

• Saturated or Unsaturated Triaxial Shear tests with different stress or strain paths
• Drying or wetting Soil-Characteristic Curves
• Hydraulic Conductivity
• Saturated or Unsaturated Consolidation
• Response to wetting
• Liquefaction
• Resilient Modulus
• Cyclic Strength

Angle of internal friction, cohesion, dilatancy, modulus of elasticity, coefficient of consolidation, coefficient of permeability, unsaturated strength parameters, resilient modulus.

Design of foundations, embankments, slopes, pavements, and liquefaction analysis.

• Patil, Ujwalkumar D., Laureano R. Hoyos, Anand J. Puppala, and Surya Sarat Chandra Congress. “Suction Stress Characteristic Curves of Cohesive-Frictional Soils from Multiple Suction-Controlled Testing Methods.” International Journal of Geomechanics 20, no. 7 (2020): 04020077.
• Banerjee, Aritra, Anand J. Puppala, Prince Kumar, and Laureano R. Hoyos. “Stress-Dilatancy of Unsaturated Soil.” In Geo-Congress 2020: Geo-Systems, Sustainability, Geoenvironmental Engineering, and Unsaturated Soil Mechanics, pp. 420-429. Reston, VA: American Society of Civil Engineers, 2020.
• Banerjee, Aritra, Anand J. Puppala, and Laureano R. Hoyos. “Suction-controlled multistage triaxial testing on clayey silty soil.” Engineering Geology 265 (2020): 105409.
• Banerjee, Aritra, Anand J. Puppala, Laureano R. Hoyos, William J. Likos, and Ujwalkumar D. Patil. “Resilient modulus of expansive soils at high suction using vapor pressure control.” Geotechnical Testing Journal 43, no. 3 (2020).
• Banerjee, Aritra, Ujwalkumar D. Patil, Anand J. Puppala, and Laureano R. Hoyos. “Suction-controlled repeated load triaxial test of subgrade soil at high suction states.” In Unsaturated Soils, Proceeding of Seventh International Conference on Unsaturated Soils. Hong Kong, China: HKUST, pp. 667-672. 2018.
• Banerjee, Aritra, Ujwalkumar D. Patil, Anand J. Puppala, and Laureano R. Hoyos. “Evaluation of Liquefaction Resistance in Silty Sand via Suction Controlled Cyclic Triaxial Tests.” In PanAm Unsaturated Soils 2017, pp. 543-552. 2018.