D5298

Designation: D 5298 – 03

Standard Test Method for

Measurement of Soil Potential (Suction) Using Filter Paper1
This standard is issued under the fixed designation D 5298; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon (e) indicates an editorial change since the last revision or reapproval.

1. Scope 1.1 This test method covers laboratory filter papers as passive sensors to evaluate the soil matric (matrix) and total potential (suction), a measure of the free energy of the pore-water or tension stress exerted on the pore-water by the soil matrix (1, 2)2. The term potential or suction is descriptive ofthe energy status of soil water. 1.2 This test method controls the variables for measurement of the water content of filter paper that is in direct contact with soil or in equilibrium with the partial pressure of water vapor in the air of an airtight container enclosing a soil specimen. The filter paper is enclosed with a soil specimen in the airtight container until moisture equilibrium isestablished; that is, the partial pressure of water vapor in the air is in equilibrium with the vapor pressure of pore-water in the soil specimen. 1.3 This test method provides a procedure for calibrating different types of filter paper for use in evaluating soil matric and total potential. 1.4 The values stated in SI units are to be regarded as the standard. The inch-pounds units given in parentheses areapproximate. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards: C 114 Test Methods for Chemical Analysis of HydraulicCement3 D 653 Terminology Relating to Soil, Rock, and Contained Fluids4
1 This test method is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.04 on Hydrologic Properties. Current edition approved June 10, 2003. Published August 2003. Originally approvd in 1992. Discontinued December 2002 and reinstated as D 5298 – 03. 2 The boldfacenumbers given in parentheses refer to a list of references at the end of the text. 3 Annual Book of ASTM Standards, Vol 04.01. 4 Annual Book of ASTM Standards, Vol 04.08.

D 1125 Test Method for Electrical Conductivity and Resistivity of Water5 D 2216 Test Method for Laboratory Determination of Water (Moisture) Content of Soil and Rock4 D 2325 Test Method for Capillary-Moisture Relationships forCoarse and Medium-Textured Soils by Porous-Plate Apparatus4 D 3152 Test Method for Capillary-Moisture Relationships for Fine-Textured Soils by Pressure-Membrane Apparatus4 D 4542 Test Method for Pore-Water Extraction and Determination of the Solute Salt Content of Soils by Refractometer4 D 4753 Specification for Evaluating, Selecting, and Specifying Balances and Scales for Use in Testing Soil, Rockand Related Construction Materials3 E 337 Test Method for Measuring Humidity With a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures6 E 832 Specification for Laboratory Filter Papers7 3. Terminology 3.1 Definitions: 3.1.1 Refer to Terminology D 653 for standard definitions of terms. 3.2 Definitions of Terms Specific to This Standard: 3.2.1 atmosphere—a unit of pressure equal to 76 cmMercury or 101 kPa at 0°C. 3.2.2 matric (matrix) suction, hm (kPa)—the negative pressure (expressed as a positive value), relative to ambient atmospheric pressure on the soil water, to which a solution identical in composition with the soil water must be subjected in order to be in equilibrium through a porous permeable wall with the soil water; pressure equivalent to that measured by Test Methods...