Estimations...

A service provided for the estimation of unsaturated soil functions from a grain-size distribution and volume-mass properties

Central to seepage modeling practice in unsaturated soils is the soil-water characteristic curve (SWCC). Laboratory testing required to determine the soil-water characteristic curve and other unsaturated soil functions can be expensive and time-consuming. Generally, all that is required for modeling purposes is an estimate of soil functions. The modeling of unsaturated soil processes such as seepage requires two unsaturated soil functions:

The soil-water characteristic curve and the hydraulic conductivity curve must be known for the modeling of seepage in unsaturated soils.

How are the estimations made?

SoilVision Systems Ltd. uses the knowledge-based system, SoilVision, to make these estimations. SoilVision makes use of estimation algorithms trained on a database totaling over 5000 different soils. These estimation techniques have been shown by research to be successful in the estimation of various unsaturated soil properties. As such, the estimation algorithms used by SoilVision have already been tried and tested in the practice and application of soils related fields.

Estimation of the soil-water characteristic curve

The estimation methods Fredlund and Wilson (1997), Gupta and Larson (1979), Arya and Paris (1981), Scheinost (1996), Rawls (1985), Vereecken (1989), Tyler and Wheatcraft (1989) are provided in the SWCC estimation. A statistical distribution of experimentally measured soil-water characteristic curves is also provided.

Estimation of the hydraulic conductivity curve

Available estimation methods for the saturated hydraulic conductivity are Hazen (1981), Kozeny-Carmen (1989), Rawls and Brakensiek (1983), and Rawls, Brakensiek, and Logsdon (1993) methods.

The entire hydraulic conductivity curve may be estimated from the following methods. Fredlund and Xing (1993), Campbell (1973), van Genuchten and Mualem (1980), or the Brooks and Corey (1964) methods.

Example estimations of the soil-water characteristic curve:

What information is needed to make the estimations?

SoilVision Systems Ltd. requires a well-defined grain-size distribution, any three volume-mass properties (i.e. porosity, dry density, and specific gravity of the soil), and a short description indicating the type of soil and any significant features. Individual estimations may require more specialized information. Please contact SoilVision Systems Ltd. for a complete description of the information required for estimations.

Prices:

$150 US per soil-water characteristic curve estimation
$120 US per hydraulic conductivity estimation


Download the estimation template(EXCEL 3.0 format), fill out the required information, and send a Message to us for instructions on how to send the template. Allow 3 to 5 days for processing.

For more information on this service please contact SoilVision Systems Ltd.