Soil-Water Characteristic Device
SWC-150 Soil-Water Characteristic Cell

The GCTS SWC-150 Soil-Water Characteristic Cell is a simple device used for testing unsaturated soil and can obtain the complete soil-water characteristic curve (SWCC) for a given soil.


  • Simulates vertical in-situ pressure state
  • Tracks volume changes
  • Tracks water content
  • Applied suctions up to 1,500 kPa
  • Both drying (de-adsorption) and wetting (adsorption) curves
  • Dual pressure gauges and regulators for precise pressure control
  • Stainless steel construction with hand-operated knobs for fast setup
  • Pressure compensator on the loading ram
  • Flushing ability and measurement of diffused air
  • Optional hanging column for applying suctions below 5 kPa
  • Optional heater for preventing vapor condensation inside the cell
  • Optional null-type initial suction measurements on undisturbed specimens available


The Fredlund SWCC Device (SWC-150) is a simple and flexible unsaturated soil testing apparatus to measure the soil water characteristic curve while applying various stress states.


The SWC-150 can be used to obtain the complete soil-water characteristic curve (SWCC) for a soil sample. The Fredlund SWCC device allows the operator to control matric suctions from near zero values up to 1,500 kPa (215 psi), and is capable of applying one-dimensional loading, Ko, to a specimen with a diameter up to 75 mm. The device is economically priced and is a complete “turn-key” system.


The cell is constructed from stainless steel and includes the necessary plumbing and valves for periodic flushing and measuring of diffused air. Several different high air-entry-value (HAEV) ceramic stones can be easily interchanged. Dead weights can be used to apply normal stresses. An optional pneumatic load frame loader is available to apply larger stresses.


Through its convenient design, the apparatus allows the use of a single soil specimen to obtain the entire SWCC with any number of data points.


  • 15 bar maximum suction
  • 71 mm maximum specimen diameter
  • 50 mm maximum specimen height


Please contact GCTS for full specifications.