1、Designation:D6572131Standard Test Methods forDetermining Dispersive Characteristics of Clayey Soils bythe Crumb Test1This standard is issued under the fixed designation D6572;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year o
2、f last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEEditorial corrections made throughout in February 2014.1.Scope*1.1 Two test methods are provided to give a qualitativeindicatio
3、n of the natural dispersive characteristics of clayeysoils:Method A and Method B.1.1.1 Method AProcedure for Natural Soil Crumbs de-scribed in 10.2.1.1.2 Method BProcedure for Remolded Soil Crumbsdescribed in 10.3.1.2 The crumb test,while a good,quick indication ofdispersive soil,should usually be r
4、un in conjunction with apinhole test and a double hydrometer test,Test Methods D4647and D4221,respectively.1.3 The crumb test has some limitations in its usefulness asan indicator of dispersive soil.Adispersive soil may sometimesgive a non-dispersive reaction in the crumb test.Soils contain-ing kaol
5、inite with known field dispersion problems,haveshown non-dispersive reactions in the crumb test(1).2However,if the crumb test indicates dispersion,the soil isprobably dispersive.1.4 These test methods are not applicable for soils with 12%or less of the particles passing 0.005 mm and having aplastici
6、ty index less than or equal to 8,as determined by TestMethod D4318.1.5 Oven-dried soil should not be used to prepare crumb testspecimens,as irreversible changes could occur to the soilpore-water physicochemical properties responsible for disper-sion(2).NOTE1In some cases,the results of the pinhole,c
7、rumb,anddouble-hydrometer test methods may disagree.The crumb test is a betterindicator of dispersive soils than of non-dispersive soils(3).1.6 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.6.1 The procedures used
8、 to specify how data are collected/recorded or calculated in this standard are regarded as theindustry 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
9、 purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease or reduce significant digits of reported data to becommensurate with these considerations.It is beyond the scopeof this standard to consider significant digits used in analyticalmethods for engineer
10、ing design.1.7 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.1.8 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 es
11、tablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3D653 Terminology Relating to Soil,Rock,and ContainedFluidsD1193 Specification for Reagent WaterD2216 Test Methods for Laboratory Determin
12、ation 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 ConstructionD4221 Test Method for Dispersive Characteristics of ClaySoil by Double Hydrometer1These test
13、methods are under the jurisdiction ofASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommittee D18.06 on Physical-Chemical Interactions of Soil and RockCurrent edition approved Nov.1,2013.Published November 2013.Originallyapproved in 2006.Last previous edition approved in
14、2012 as D4186 12.DOI:10.1520/D6572-13E01.2The boldface numbers in parentheses refer to the 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 infor
15、mation,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 D4318 Test Methods for Liquid Limit,Plastic Limit,andP
16、lasticity Index of SoilsD4647 Test Method for Identification and Classification ofDispersive Clay Soils by the Pinhole TestD6026 Practice for Using Significant Digits in GeotechnicalDataE1 Specification for ASTM Liquid-in-Glass ThermometersE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision Liquids3.Terminology3.1 Definitions:3.1.1 For definitions of common technical terms in thisstandard,refer to Te