1、Designation:D495916Standard Test Method forDetermination of Water Content of Soil By Direct Heating1This standard is issued under the fixed designation D4959;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A
2、 number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers procedures for determining thewater content of soils by drying with direct heat,such as usinga hotplate,stove,blo
3、wtorch,and the like.1.2 This test method can be used as a substitute for TestMethods D2216 when more rapid results are desired toexpedite other phases of testing and slightly less accurateresults are acceptable.1.3 When questions of accuracy between this test methodand Test Methods D2216 arise,Test
4、Methods D2216 shall bethe referee method.1.4 This test method is applicable for most soil types.Forsome soils,such as those containing significant amounts ofhalloysite,mica,montmorillonite,gypsum,or other hydratedmaterials,highly organic soils or soils that contain dissolvedsolids,(such as salt in t
5、he case of marine deposits),this testmethod may not yield reliable water content values due to thepotential for heating above 110C or lack of means to accountfor the presence of precipitated solids that were previouslydissolved.1.5 The values stated in SI units are to be regarded asstandard.Performa
6、nce of the test method utilizing anothersystem of units shall not be considered non-conformance.Thesieve designations are identified using the“standard”system inaccordance with Specification E11,such as 2.0-mm and19-mm,followed by the“alternative”system of No.10 and34-in.,respectively,in parentheses
7、.1.6 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inD6026,unless otherwise superseded by this standard.1.6.1 The procedures used to specify how data are collected/recorded or calculated,in this standard are regarded as theindustry
8、standard.In addition,they are representative of thesignificant digits that generally should be retained.The proce-dures used do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease o
9、r reduce significant digits of reported data to becommensurate with these considerations.It is beyond the scopeof this standard to consider significant digits used in analysismethods for engineering design.1.6.2 Significant digits are especially important if the watercontent will be used to calculat
10、e other relationships such asmoist mass to dry mass or vice versa,wet unit weight to dryunit weight or vice versa,and total density to dry density orvice versa.For example,if four significant digits are requiredin any of the above calculations,then the water content has tobe recorded to the nearest
11、0.1%,for water contents below100%.This occurs since 1 plus the water content(not inpercent)will have four significant digits regardless of what thevalue of the water content is(below 100%);that is,1 plus0.1/100=1.001,a value with four significant digits.While,ifthree significant digits are acceptabl
12、e,then the water contentcan be recorded to the nearest 1%.1.7 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
13、 of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD2216 Test Methods for Laboratory Determination of Water(Moisture)Content of Soil and Rock by MassD3740 Practice for Minimum Requirements for AgenciesEngaged in
14、 Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4753 Guide for Evaluating,Selecting,and Specifying Bal-ances and Standard Masses for Use in Soil,Rock,andConstruction Materials TestingD6026 Practice for Using Significant Digits in GeotechnicalData1This test m
15、ethod is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.08 on Special andConstruction Control Tests.Current edition approved Jan.1,2016.Published January 2016.Originallyapproved in 1989.Last previous edition approved in 2007 as D4959
16、07.DOI:10.1520/D4959-16.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 E11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.T