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TRIM Device

The TRIM System is a simple-to-use laboratory device for measuring the soil-water retention curve (SWRC) and hydraulic conductivity function (HCF) of unsaturated soils in significantly less time than other approaches. The SWRC and HCF may be measured along either wetting or drying paths in as little as 5-7 days using either disturbed or undisturbed samples. The system may be operated in either steady-state mode or transient mode and is applicable for all major soil types, including sand, silts, and clays.


  • Precision flow cell with integrated high-air-entry (HAE) base (6,000 psf)
  • Capability to extrapolate suction range to several thousand psf
  • Visual bubble trap system to account for diffused air volume
  • Control panel for dual-range air-pressure (< or > 300 psf) control
  • Vacuum control (option) for in-situ sample and HAE disk saturation
  • Integrated pore-fluid reservoir
  • Electronic balance for automated monitoring of pore fluid volume.
  • Control computer (option) and graphical user interface for data acquisition and post-processing.
  • Manufactured with high-quality components and stainless steel fittings.
  • Undisturbed or remolded specimen with dimensions of 2.0 inches to 5.5 inches in diameter x 2 inches to 4 inches in height.
  • Completion of both wetting and drying SWCC and HCF in one week.
  • Post processing software (HYDRUS-1D TRIM) for easy data reduction and parameter analysis.

For more information about this device please click here.