1、Designation: D 7382 07Standard 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 D 7382; the number immediately following the designation indicates the
2、 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the determination of them
3、aximum 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
4、 the 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 D 4718.1.6 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
7、moisture-density relationship is not apparent.However, for some soils containing more than 15 % fines, theuse of impact compaction (Test Methods D 698 or D 1557)may be useful in evaluating what is an appropriate maximumindex density/unit weight.1.7 Two alternative test methods are provided, with the
8、variation 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. (
9、19.0-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 LayersThr
10、ee.1.7.2.4 Time of Compaction per layer52 6 5 s at each of8 locations.NOTE 2Method A (with the correction procedure of Practice D 4718,if appropriate), has been shown (reference thesis or paper) to provideconsistent results with Method B. Therefore, for ease of operations, it ishighly recommended to
11、 use Method A, unless Method B is required dueto soil gradations not meeting Practice D 4718.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 o
12、r wet/saturated 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
13、 theappropriate field in-place density test specimen using PracticeD 4718.1.9 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 o
14、btainedwhen 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
15、 are to be regarded separately as standard. Thevalues stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1These test methods are under the jurisdictio
16、n of ASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommittee D18.03 on Texture,Plasticity and Density Characteristics of Soils.Current edition approved Sept. 1, 2007. Published October 2007.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
17、ken, PA 19428-2959, United States.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 to establish appro
18、priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateC 136 Test Method for Sieve Analysis of Fine and
19、 CoarseAggregatesC 778 Specification for Standard SandD 422 Test Method for Particle-Size Analysis of SoilsD 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 698 Test Methods for Laboratory Compaction Character-istics of Soil Using Standard Effort (12 400 ft-lbf/ft3(600kN-m/m3)D 854 Test
20、 Methods for Specific Gravity of Soil Solids byWater PycnometerD 1140 Test Methods for Amount of Material in Soils Finerthan No. 200 (75-m) SieveD 1557 Test Methods for Laboratory Compaction Charac-teristics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)D 2216 Test Methods for Labor
21、atory Determination of Wa-ter (Moisture) Content of Soil and Rock by MassD 2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)D 2488 Practice for Description and Identification of Soils(Visual-Manual Procedure)D 3282 Practice for Classification of S
22、oils and Soil-Aggregate Mixtures for Highway Construction PurposesD 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 4220 Practices for Preserving and Transporting SoilSamplesD 4253 Test Method
23、s for Maximum Index Density and UnitWeight of Soils Using a Vibratory TableD 4254 Test Methods for Minimum Index Density and UnitWeight of Soils and Calculation of Relative DensityD 4318 Test Methods for Liquid Limit, Plastic Limit, andPlasticity Index of SoilsD 4718 Practice for Correction of Unit
24、Weight and WaterContent for Soils Containing Oversize ParticlesD 4753 Guide for Evaluating, Selecting, and SpecifyingBalances and Standard Masses for Use in Soil, Rock, andConstruction Materials TestingD 6026 Practice for Using Significant Digits in Geotechni-cal DataE11 Specification for Wire Cloth
25、 and Sieves for TestingPurposesE 145 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:3M092-05-UL Standa
26、rd 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 Definitions:3.1
27、1 For definitions of terms used in this test method, referto Terminology D 653.3.2 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 of the li
28、quid 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 percentag
29、e, 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 compaction
30、test; 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 maximum dry u
31、nit 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.Each layer is compacted for a given amount of time by avibrating hammer that applies v
32、ibration 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 soil. The water content range for effective2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custome
33、r 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, DC 20001,http:
34、/www.transportation.org.D7382072compaction 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 of a give
35、n 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 often compa
36、cted 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 unit weigh
37、ts 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, com-pressibility, and permeability of a given soil, compacted byvarious methods to a giv
38、en 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 implement oryie
39、ld 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, especi
40、ally 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 not repr
41、esentative 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 compaction,fol
42、lowed 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 earthworkproject, espec
43、ially 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 than us
44、ual.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 poor result
45、s 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 reach asatu
46、rated 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 necessarilyobtained by t
47、hese 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 D 3740 are generally considered capable of competentand object
48、ive testing/sampling/inspection, and the like. Users of thisstandard are cautioned that compliance with Practice D 3740 does not initself assure reliable results. Reliable results depend on many factors;Practice D 3740 provides a means of evaluating some of those factors.6. Apparatus6.1 Vibrating Ha
49、mmerThe 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 impact energy shall be in the range of 7 to 9 ft-lbf(9.5 to 12 m-N) and weigh 12 to 20 lbf (53 to 89 N), notincluding the weight of the tamper.NOTE 6It has been found that a Bosch model 11248EVS will providethe above specified characteristics. Other vibrating hammers also mayprovide satisfactory compaction and may b
