1、Designation: D7382 08Standard Test Methods forDetermination of Maximum Dry Unit Weight and WaterContent Range for Effective Compaction of Granular SoilsUsing a Vibrating Hammer1This standard is issued under the fixed designation D7382; the number immediately following the designation indicates the y
2、ear 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. Scope*1.1 These test methods cover the determination of themax
3、imum dry unit weight and water content range for effectivecompaction of granular soils. A vibrating hammer is used toimpart a surcharge and compactive effort to the soil specimen.1.2 These test methods apply to soils with up to 35 %, bydry mass, passing a No. 200 (75-m) sieve if the portionpassing t
4、he No. 40 (425-m) sieve is nonplastic.1.3 These test methods apply to soils with up to 15 %, bydry mass, passing a No. 200 (75-m) sieve if the portionpassing the No. 40 (425-m) sieve exhibits plastic behavior.1.4 These test methods apply to soils in which 100 %, bydry mass, passes the 2-in. (50-mm)
5、sieve.1.5 These test methods apply only to soils (materials) thathave 30 % or less, by dry mass of their particles retained on the34-in. (19.0-mm) sieve.NOTE 1For relationships between unit weights and water contents ofsoils with 30 % or less, by dry mass, of material retained on the34-in.(19.0-mm)
6、sieve to unit weights and water contents of the fraction passingthe34-in. (19.0-mm) sieve, see Practice D4718.1.6 These test methods will typically produce a highermaximum dry density/unit weight for the soils specified in 1.2and 1.3 than that obtained by impact compaction in which awell-defined moi
7、sture-density relationship 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 indexdensity/unit weight.1.7 Two alternative test methods are provided, with thevaria
8、tion being in mold size. The method used shall be asindicated in the specification for the material being tested. If nomethod is specified, the choice should be based on themaximum particle size of the material.1.7.1 Method A:1.7.1.1 Mold6-in. (152.4-mm) diameter.1.7.1.2 MaterialPassing34-in. (19.0-
9、mm) sieve and con-sistent with the requirements of 1.2 and 1.3.1.7.1.3 LayersThree.1.7.1.4 Time of Compaction per layer60 6 5s.1.7.2 Method B:1.7.2.1 Mold11-in. (279.4-mm) diameter.1.7.2.2 MaterialPassing 2-in. (50-mm) sieve and consis-tent with the requirements of 1.2 and 1.3.1.7.2.3 LayersThree.1.
10、7.2.4 Time of Compaction per layer52 6 5 s at each of8 locations.NOTE 2Method A (with the correction procedure of Practice D4718,if appropriate), has been shown (reference thesis or paper) to provideconsistent results with Method B. Therefore, for ease of operations, it ishighly recommended to use M
11、ethod A, unless Method B is required dueto soil gradations not meeting Practice D4718.NOTE 3Results have been found to vary slightly when a material istested at the same compaction effort in different size molds.1.7.3 Either method, A or B, can be performed with thematerial in an oven-dried or wet/s
12、aturated state, whicheverprovides the maximum dry unit weight.1.8 If the test specimen contains more than 5 % by mass ofoversize fraction (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 theapp
13、ropriate field in-place density test specimen using PracticeD4718.1.9 This test method causes a minimal amount of degrada-tion (particle breakdown) of the soil. When degradation occurs,typically there is an increase in the maximum unit weightobtained, and comparable test results may not be obtainedw
14、hen different size molds are used to test a given soil. For soilswhere degradation is suspected, a sieve analysis of the speci-men should be performed before and after the compaction testto determine the amount of degradation.1.10 UnitsThe values stated in either SI units or inch-pound units are to
15、be regarded separately as standard. Thevalues stated in each system may not be exact equivalents;1These test methods are under the jurisdiction of ASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommittee D18.03 on Texture,Plasticity and Density Characteristics of Soils.Cu
16、rrent edition approved Nov. 1, 2008. Published November 2008. Originallyapproved in 2007. Last previous edition approved in 2007 as D7382 07. DOI:10.1520/D7382-08.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West C
17、onshohocken, PA 19428-2959. United StatesNOTICE: This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International (www.astm.org) for the latest information1therefore, each system shall be used independently of the other.Combining values from the two syst
18、ems may result in non-conformance with the standard.1.11 The vibrating hammer test method may be performedin the field or in the laboratory.1.12 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
19、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:2C127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateC136 Test Method for Sieve Anal
20、ysis of Fine and CoarseAggregatesC778 Specification for SandD422 Test Method for Particle-Size Analysis of SoilsD653 Terminology Relating to Soil, Rock, and ContainedFluidsD698 Test Methods for Laboratory Compaction Character-istics of Soil Using Standard Effort (12 400 ft-lbf/ft3(600kN-m/m3)D854 Te
21、st Methods for Specific Gravity of Soil Solids byWater PycnometerD1140 Test Methods for Determining the Amount of Mate-rial Finer than 75-m (No. 200) Sieve in Soils by WashingD1557 Test Methods for Laboratory Compaction Character-istics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)
22、D2216 Test Methods for Laboratory Determination of Water(Moisture) Content of Soil and Rock by MassD2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)D2488 Practice for Description and Identification of Soils(Visual-Manual Procedure)D3282 Practice
23、for Classification of Soils and Soil-Aggregate Mixtures for Highway Construction PurposesD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4220 Practices for Preserving and Transporting SoilSamplesD
24、4253 Test Methods for Maximum Index Density and UnitWeight of Soils Using a Vibratory TableD4254 Test Methods for Minimum Index Density and UnitWeight of Soils and Calculation of Relative DensityD4318 Test Methods for Liquid Limit, Plastic Limit, andPlasticity Index of SoilsD4718 Practice for Correc
25、tion of Unit Weight and WaterContent for Soils Containing Oversize ParticlesD4753 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 GeotechnicalDataE11 Specification for
26、 Woven Wire Test Sieve Cloth and TestSievesE145 Specification for Gravity-Convection and Forced-Ventilation OvensIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI): the Modern Metric System2.2 American Association of State Highway and Transpor-tation Offcials Standards:3M092-0
27、5-UL Standard Specification for Wire-Cloth Sievesfor Testing PurposesM145-91-UL Standard Specification for Classification ofSoils and Soil-Aggregate Mixtures for Highway Construc-tion PurposesM231-95-UL Standard Specification for Weighing DevicesUsed in the Testing of Materials3. Terminology3.1 Defi
28、nitions:3.1.1 For definitions of terms used in this test method, referto Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 granular soil, nany soil with less than 35 %, by drymass, passing the No. 200 (75-m) sieve.3.2.2 nonplastic, adjdescription for a soil sample whenany one
29、 of the liquid limit, plastic limit, or plasticity index cannot be determined.3.2.3 plastic, adjdescription for a soil sample when theliquid limit, plastic limit, and plasticity index can all bedetermined.3.2.4 water content range for effective compaction, ntherange of water contents, expressed as a
30、 percentage, bounded by80 % of wZAVand wZAV.3.2.5 zero air voids water content, wZAV,nthe watercontent, expressed as a percentage, that corresponds to satura-tion at the maximum dry unit weight.3.2.6 oversize fraction (coarse fraction), Pc(%), ntheportion of total sample not used in performing the c
31、ompactiontest; it is the portion of total sample retained the34-in.(19.0-mm) sieve.3.2.7 test fraction (finer fraction), Pf(%), nthe portion oftotal sample used in performing the compaction test; it is theportion of total sample passing the34-in. (19.0-mm) sieve.4. Summary of Test Method4.1 The maxi
32、mum dry unit weight and water content rangefor effective compaction of a given free-draining soil isdetermined using either an oven-dried or wet/saturated soil.Soil is placed in three layers into a mold of given dimensions.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orconta
33、ct 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 American Association of State Highway and TransportationOfficials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington,
34、 DC 20001,http:/www.transportation.org.D7382 082Each layer is compacted for a given amount of time by avibrating hammer that applies vibration and surcharge to thesoil. The dry unit weight is calculated by dividing the oven-dried weight of the densified soil by the volume of the moldcontaining the s
35、oil. The water content range for effectivecompaction is determined from the maximum dry unit weightand the specific gravity of solids.5. Significance and Use5.1 For many cohesionless, free-draining soils, the maxi-mum dry unit weight is one of the key components inevaluating the state of compactness
36、 of a given soil mass that iseither naturally occurring or is constructed (fill).5.2 Soil placed as an engineered fill is compacted to a densestate to obtain satisfactory engineering properties such as shearstrength, compressibility, permeability, or combinationsthereof. Also, foundation soils are o
37、ften compacted to improvetheir engineering properties. Laboratory compaction tests pro-vide the basis for determining the percent compaction andwater content needed at the time of compaction to achieve therequired engineering properties, and for controlling construc-tion to assure that the required
38、unit weights and water contentsare achieved.5.3 It is generally recognized that percent compaction is agood indicator of the state of compactness of a given soil mass.However, the engineering properties, such as strength,compressibility, and permeability of a given soil, compacted byvarious methods
39、to a given state of compactness can varyconsiderably. Therefore, considerable engineering judgmentmust be used in relating the engineering properties of soil to thestate of compactness.5.4 Experience indicates that the construction control as-pects discussed in 5.2 are extremely difficult to impleme
40、nt oryield erroneous results when dealing with certain soils. 5.4.1,5.4.2, and 5.4.3 describe typical problem soils, the problemsencountered when dealing with such soils, and possible solu-tions to these problems.5.4.1 DegradationSoils containing particles that degradeduring compaction are a problem
41、, especially when moredegradation occurs during laboratory compaction than fieldcompaction, as is typical. Degradation typically occurs duringthe compaction of a granular-residual soil or aggregate. Whendegradation occurs, the maximum dry unit weight increases4sothat the laboratory maximum value is
42、not representative of fieldconditions. Often, in these cases, the maximum dry unit weightis impossible to achieve in the field.5.4.1.1 One method to design and control the compaction ofsuch soils is to use a test fill to determine the required degreeof compaction and the method to obtain that compac
43、tion,followed by the use of a method specification to control thecompaction. Components of a method specification typicallycontain the type and size of compaction equipment to be used,the lift thickness, and the number of passes.NOTE 4Success in executing the compaction control of an earthworkprojec
44、t, especially when a method specification is used, is highlydependent upon the quality and experience of the “contractor” and“inspector.”5.4.2 Gap GradedGap-graded soils (soils containingmany large particles with limited small particles) are a problembecause the compacted soil will have larger voids
45、 than usual.To handle these large voids, standard test methods (laboratoryor field) typically have to be modified using engineeringjudgment.5.4.3 Gravelly Soils Possessing Low Angularity and HighPercentage of FinesGravelly soils possessing low angularityand a high percentage of fines can lead to poo
46、r results for dryunit weight when using the wet/saturated method. However,when water contents at the time of compaction are nearsaturation with no free water, the dry unit weight achieved mayresult in a higher value than that from the dry method.Ultimately, during densification, the material may rea
47、ch asaturated state. Therefore, for these soils, a water content of 1or 2 % less than the wzavfor the density achieved by using thedry method is recommended. This is more of a concern fortesting in the 11-in. mold than in the 6-in. mold.5.5 An absolute maximum dry unit weight is not necessarilyobtai
48、ned by these test methods.NOTE 5The quality of the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D3740 are generally considered capable of competentand
49、 objective testing/sampling/inspection, and the like. Users of thisstandard are cautioned that compliance with Practice D3740 does not initself assure reliable results. Reliable results depend on many factors;Practice D3740 provides a means of evaluating some of those factors.6. Apparatus6.1 Vibrating HammerThe vibrating hammer used for thistest should be one that is commercially available and providesreliable performance. The vibration hammer shall operate at afrequency of 3200 to 3500 beats per minute and the manufac-turers rated
