1、Designation:D738220Standard Test Methods forDetermination of Maximum Dry Unit Weight of GranularSoils Using a Vibrating Hammer1This standard is issued under the fixed designation D7382;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,
2、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.Scope*1.1 These test methods cover the determination of themaximum dry unit weight of granular soils.A vibratinghammer i
3、s used to impart a surcharge and compactive effort tothe soil specimen.Further,an optional calculation is presentedto determine the approximate water content range for effectivecompaction of granular soils based on the measured maximumdry density and specific gravity.1.2 These test methods apply to
4、primarily granular,free-draining soils for which impact compaction does not yield aclear optimum water content.Specifically,these test methodsapply to soils:1.2.1 with up to 35%,by dry mass,passing a No.200(75-m)sieve if the portion passing the No.40(425-m)sieveis nonplastic;1.2.2 with up to 15%,by
5、dry mass,passing a No.200(75-m)sieve if the portion passing the No.40(425-m)sieveexhibits plastic behavior.1.3 Further,due to limitations of the testing equipment,andthe available oversize correction procedures these test methodsapply to soils in which:1.3.1 less than 30%,by dry mass,is retained on
6、the34-in.(19.0-mm)sieve,or in which1.3.2 100%,by dry mass,passes the 2-in.(50-mm)sieve.1.4 These test methods will typically produce a highermaximum dry unit weight for the soils specified in 1.2.1 and1.2.2 than that obtained by impact compaction in which awell-defined moisture-density relationship
7、is not apparent.However,for some soils containing more than 15%fines,theuse of impact compaction(Test Methods D698 or D1557)maybe useful in evaluating what is an appropriate maximum indexunit weight.1.5 Four alternative test methods are provided,with thevariation being in saturated versus dry specim
8、ens and moldsize.The method used shall be as indicated in the specificationfor the material being tested.If no method is specified,thechoice should be based on the maximum particle size of thematerial.1.5.1 Method 1AUsing saturated material and a 6-in.(152.4-mm)diameter mold;applicable for materials
9、 withmaximum particle size of34-in.(19-mm)or less,or with 30%or less,by dry mass,retained on the34-in.(19-mm)sieve.1.5.2 Method 1BUsing saturated material and an 11-in.(279.4-mm)diameter mold;applicable for materials withmaximum particle size of 2-in.(50-mm)or less1.5.3 Method 2AUsing oven-dry mater
10、ial and a 6-in.(152.4-mm)diameter mold;applicable for materials withmaximum particle size of34-in.(19-mm)or less,or with 30%or less,by dry mass,retained on the34-in.(19-mm)sieve.1.5.4 Method 2BUsing oven-dry material and an 11-in.(279.4-mm)diameter mold;applicable for materials withmaximum particle
11、size of 2-in.(50-mm)or less.1.5.5 It is recommended that both the saturated and drymethods(Methods 1A and 2A,or 1B and 2B)be performedwhen beginning a new job or encountering a change in soiltype,as one method or the other may result in a higher valuefor the maximum dry unit weight.While the dry met
12、hod isoften preferred for convenience and because results can beobtained more quickly,as a general rule,the saturated methodshould be used if it proves to produce a significantly highervalue for maximum dry unit weight.NOTE1Results have been found to vary slightly when a material istested at the sam
13、e compaction effort in different size molds.1.6 If the test specimen contains more than 5%by mass ofoversize material(coarse fraction)and the material will not beincluded in the test,corrections must be made to the unitweight and water content of the test specimen or to theappropriate field in-place
14、 density test specimen using PracticeD4718.NOTE2Methods 1Aand 2A(with the correction procedure of PracticeD4718,if appropriate),have been shown to provide consistent results withMethods 1B and 2B for materials with 30%or less,by dry mass retainedon the34-in.(19-mm)sieve.Therefore,for ease of operati
15、ons,it isrecommended to use Method 1A or 2A,unless Method 1B or 2B isrequired due to soil gradations having in excess of 30%,by dry mass,retained on the34-in.(19-mm)sieve.1These test methods are under the jurisdiction ofASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommi
16、ttee D18.03 on Texture,Plasticity and Density Characteristics of Soils.Current edition approved July 1,2020.Published July 2020.Originally approvedin 2007.Last previous edition approved in 2008 as D7382 08,which waswithdrawn in February 2017 and reinstated July 2020.DOI:10.1520/D7382-20.*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 StatesThis international standard was develop