Standard Test Methods for Determination of the Soil Water Characteristic Curve

Importancia y uso:

5.1 The SWCC is fundamental to hydrological characterization of unsaturated soils and is required for most analyses of water movement in unsaturated soils. The SWCC is also used in characterizing the shear strength and compressibility of unsaturated soils. The unsaturated hydraulic conductivity of soil is often estimated using properties of the SWCC and the saturated hydraulic conductivity. Using Method F, the unsaturated hydraulic conductivity can be determined directly, although the calculations necessary for this direct determination are outside the scope of this standard.

5.2 This method applies only to soils containing two pore fluids: a gas and a liquid. The liquid is usually water and the gas is usually air. Other liquids may also be used, but caution must be exercised if the liquid being used causes excessive shrinkage or swelling of the soil matrix.

5.3 A full investigation has not been conducted regarding the correlation between soil water characteristic curves obtained using this method and soil water characteristics curves of in-place materials. Thus, results obtained from this method should be applied to field situations with caution and by qualified personnel.

Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it and the suitability of the equipment and facility used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some, but not all, of those factors.

Subcomité:

D18.04

Referida por:

D7664-10R18E01, D7294-13R21, E3282-22, E3268-21

Volúmen:

04.09

Número ICS:

13.080.40 (Hydrological properties of soil)

Palabras clave:

air entry point; capillary pressure; chilled mirror hygrometer; evaporation; gravimetric water content; hanging column; matric potential; matric suction; pressure membrane; pressure plate; soil; soil water characteristic curve; suction; total suction; volumetric water content; water activity;