ASTM_D_5298_-_10.pdf

Designation:D529810Standard Test Method forMeasurement of Soil Potential(Suction)Using Filter Paper1This standard is issued under the fixed designation D5298;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers laboratory filter papers aspassive sensors to evaluate the soil matric(matrix)and totalpotential(suction),a measure of the free energy of thepore-water or tension stress exerted on the pore-water by thesoil matrix(1,2).2The term potential or suction is descriptiveof the energy status of soil water.1.2 This test method controls the variables for measurementof the water content of filter paper that is in direct contact withsoil or in equilibrium with the partial pressure of water vaporin the air of an airtight container enclosing a soil specimen.Thefilter paper is enclosed with a soil specimen in the airtightcontainer until moisture equilibrium is established;that is,thepartial pressure of water vapor in the air is in equilibrium withthe vapor pressure of pore-water in the soil specimen.1.3 This test method provides a procedure for calibratingdifferent types of filter paper for use in evaluating soil matricand total potential.1.4 The values stated in SI units are to be regarded asstandard.The inch-pound units given in parentheses areapproximate.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3C114 Test Methods for Chemical Analysis of HydraulicCementD653 Terminology Relating to Soil,Rock,and ContainedFluidsD1125 Test Methods for Electrical Conductivity and Resis-tivity of WaterD2216 Test Methods for Laboratory Determination of Water(Moisture)Content of Soil and Rock by MassD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4542 Test Method for Pore Water Extraction and Determi-nation of the Soluble Salt Content of Soils by Refracto-meterD4753 Guide for Evaluating,Selecting,and Specifying Bal-ances and Standard Masses for Use in Soil,Rock,andConstruction Materials TestingD6836 Test Methods for Determination of the Soil WaterCharacteristic Curve for Desorption Using HangingColumn,Pressure Extractor,Chilled Mirror Hygrometer,or CentrifugeE1 Specification for ASTM Liquid-in-Glass ThermometersE337 Test Method for Measuring Humidity with a Psy-chrometer(the Measurement of Wet-and Dry-Bulb Tem-peratures)E832 Specification for Laboratory Filter PapersE1137/E1137M Specification for Industrial Platinum Resis-tance ThermometersE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision Liquids3.Terminology3.1 Definitions:3.1.1 For common definitions of technical terms in thisstandard,refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 atmospherea unit of pressure equal to 76 cm Mer-cury or 101 kPa at 0 C.3.2.2 matric(matrix)suction,hm(kPa)the negative pres-sure(expressed as a positive value),relative to ambientatmospheric pressure on the soil water,to which a solutionidentical in composition with the soil water must be subjectedin order to be in equilibrium through a porous permeable wallwith the soil water;pressure equivalent to that measured byTest Methods D6836.Matric suction is a function of therelative humidity due to the difference in air and water pressure1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.04 on HydrologicProperties and Hydraulic Barriers.Current edition approved July 1,2010.Published August 2010.Originallyapproved in 1992.Discontinued December 2002 and reinstated as D529803.Lastprevious edition approved in 2003 as D529803.DOI:10.1520/D5298-10.2The boldface numbers in parentheses refer to a list of references at the end ofthis standard.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 across the water surface;the relative humidity or water vaporpressure decreases as the radius of curvature of the watersurface decreases.The term“matric”is grammatically correct,while matrix is commonly used in the civil engineeringliterature.3.2.3 molality,moles/1000 gnumber of moles of soluteper 1000 g of solvent.3.2.4 molemolecular weight of a