ASTM_D_422_-_63_2007e2.pdf

Designation:D42263(Reapproved 2007)2Standard Test Method forParticle-Size Analysis of Soils1This standard is issued under the fixed designation D422;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.1NOTEEditorial changes made throughout in February 2014.2NOTEFurther editorial corrections made in July 2014.1.Scope1.1 This test method covers the quantitative determinationof the distribution of particle sizes in soils.The distribution ofparticle sizes larger than 75 m(retained on the No.200 sieve)is determined by sieving,while the distribution of particle sizessmaller than 75 m is determined by a sedimentation process,using a hydrometer to secure the necessary data(Note 1 andNote 2).NOTE1Separation may be made on the No.4(4.75-mm),No.40(425-m),or No.200(75-m)sieve instead of the No.10.For whateversieve used,the size shall be indicated in the report.NOTE2Two types of dispersion devices are provided:(1)a high-speed mechanical stirrer,and(2)air dispersion.Extensive investigationsindicate that air-dispersion devices produce a more positive dispersion ofplastic soils below the 20-m size and appreciably less degradation on allsizes when used with sandy soils.Because of the definite advantagesfavoring air dispersion,its use is recommended.The results from the twotypes of devices differ in magnitude,depending upon soil type,leading tomarked differences in particle size distribution,especially for sizes finerthan 20 m.2.Referenced Documents2.1 ASTM Standards:2D421 Practice for Dry Preparation of Soil Samples forParticle-Size Analysis and Determination of Soil Con-stantsE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE100 Specification for ASTM Hydrometers2.2 ASTM Adjuncts:Air-Jet Dispersion Cup for Grain-Size Analysis of Soil33.Apparatus3.1 BalancesA balance sensitive to 0.01 g for weighingthe material passing a No.10(2.00-mm)sieve,and a balancesensitive to 0.1%of the mass of the sample to be weighed forweighing the material retained on a No.10 sieve.3.2 Stirring ApparatusEither apparatus A or B may beused.3.2.1 Apparatus A shall consist of a mechanically operatedstirring device in which a suitably mounted electric motor turnsa vertical shaft at a speed of not less than 10 000 rpm withoutload.The shaft shall be equipped with a replaceable stirringpaddle made of metal,plastic,or hard rubber,as shown in Fig.1.The shaft shall be of such length that the stirring paddle willoperate not less than34in.(19.0 mm)nor more than 112in.(38.1 mm)above the bottom of the dispersion cup.A specialdispersion cup conforming to either of the designs shown inFig.2 shall be provided to hold the sample while it is beingdispersed.3.2.2 Apparatus B shall consist of an air-jet dispersion cup(see drawing in 2.23)(Note 3)conforming to the general detailsshown in Fig.3(Note 4 and Note 5).NOTE3The amount of air required by an air-jet dispersion cup is ofthe order of 2 ft3/min;some small air compressors are not capable ofsupplying sufficient air to operate a cup.NOTE4Another air-type dispersion device,known as a dispersiontube,developed by Chu and Davidson at Iowa State College,has beenshown to give results equivalent to those secured by the air-jet dispersioncups.When it is used,soaking of the sample can be done in thesedimentation cylinder,thus eliminating the need for transferring theslurry.When the air-dispersion tube is used,it shall be so indicated in thereport.NOTE5Water may condense in air lines when not in use.This watermust be removed,either by using a water trap on the air line,or byblowing the water out of the line before using any of the air for dispersionpurposes.3.3 HydrometerAn ASTM hydrometer,graduated to readin either specific gravity of the suspension or grams per litre ofsuspension,and conforming to the requirements for hydrom-eters 151H or 152H in Specifications E100.Dimensions ofboth hydrometers are the same,the scale being the only item ofdifference.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.03 on Texture,Plasticityand Density Characteristics of Soils.Current edition approved Oct.15,2007.Published October 2007.Originallyapproved in 1935.Last previous edition approved in 2002 as D422 63(2002)1.DOI:10.1520/D0422-63R07E02.2For 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.3Available from ASTM International Headquarters.Order Adjunct No.ADJD0422.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.4 Sedimentation CylinderAglass cylinder essentially 1