1、Designation: D 1557 02e1Standard Test Methods forLaboratory Compaction Characteristics of Soil UsingModified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)1This standard is issued under the fixed designation D 1557; the number immediately following the designation indicates the year oforiginal adoption or
2、, 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.This standard has been approved for use by agencies of the Department of Defense.e1NOTEPar
3、agraph 10.4.3 was corrected editorially in November 2003.1. Scope*1.1 These test methods cover laboratory compaction meth-ods used to determine the relationship between water contentand dry unit weight of soils (compaction curve) compacted ina 4- or 6-in. (101.6 or 152.4 mm) diameter mold with a 10-
4、lbf.(44.5-N) rammer dropped from a height of 18 in. (457 mm)producing a compactive effort of 56,000 ft-lbf/ft3(2,700kN-m/m3).NOTE 1Soils and soil-aggregate mixtures should be regarded asnatural occurring fine- or coarse-grained soils or composites or mixturesof natural soils, or mixtures of natural
5、and processed soils or aggregatessuch as silt, gravel, or crushed rock.NOTE 2The equipment and procedures are the same as proposed bythe U.S. Corps of Engineers in 1945. The modified effort test (see 3.2.2)is sometimes referred to as the Modified Proctor Compaction Test.1.2 These test methods apply
6、only to soils (materials) thathave 30 % or less by mass of their particles retained on the34-in. (19.0-mm) sieve.NOTE 3For relationships between unit weights and water contents ofsoils with 30 % or less by weight of material retained on the34-in.(19.0-mm) sieve to unit weights and water contents of
7、the fraction passingthe34-in. (19.0-mm) sieve, see Practice D 4718.1.3 Three alternative methods are provided. The methodused shall be as indicated in the specification for the materialbeing tested. If no method is specified, the choice should bebased on the material gradation.1.3.1 Method A:1.3.1.1
8、 Mold4-in. (101.6-mm) diameter.1.3.1.2 MaterialPassing No. 4 (4.75-mm) sieve.1.3.1.3 LayersFive.1.3.1.4 Blows per layer25.1.3.1.5 UseMay be used if 20 % or less by mass of thematerial is retained on the No. 4 (4.75-mm) sieve.1.3.1.6 Other UseIf this method is not specified, materialsthat meet these
9、gradation requirements may be tested usingMethods B or C.1.3.2 Method B:1.3.2.1 Mold4-in. (101.6-mm) diameter.1.3.2.2 MaterialPassing38-in. (9.5-mm) sieve.1.3.2.3 LayersFive.1.3.2.4 Blows per layer25.1.3.2.5 UseShall be used if more than 20 % by mass ofthe material is retained on the No. 4 (4.75-mm)
10、 sieve and 20 %or less by mass of the material is retained on the38-in.(9.5-mm) sieve.1.3.2.6 Other UseIf this method is not specified, materialsthat meet these gradation requirements may be tested usingMethod C.1.3.3 Method C:1.3.3.1 Mold6-in. (152.4-mm) diameter.1.3.3.2 MaterialPassing34-in. (19.0
11、-mm) sieve.1.3.3.3 LayersFive.1.3.3.4 Blows per layer56.1.3.3.5 UseShall be used if more than 20 % by mass ofthe material is retained on the38-in. (9.53-mm) sieve and lessthan 30 % by mass of the material is retained on the34-in.(19.0-mm) sieve.1.3.4 The 6-in. (152.4-mm) diameter mold shall not be u
12、sedwith Method A or B.NOTE 4Results have been found to vary slightly when a material istested at the same compactive effort in different size molds.1.4 If the test specimen contains more than 5 % by mass ofoversize fraction (coarse fraction) and the material will not beincluded in the test, correcti
13、ons must be made to the unitweight and water content of the test specimen or to theappropriate field in place density test specimen using PracticeD 4718.1This standard is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.03 on Texture,
14、Plasticityand Density Characteristics of Soils.Current edition approved Nov. 13, 2003. Published January 2003. Originallypublished as D 1557 58. Last previous edition D 1557 00.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO
15、Box C700, West Conshohocken, PA 19428-2959, United States.1.5 This test method will generally produce well definedmaximum dry unit weight for non-free draining soils. If thistest method is used for free draining soils the maximum unitweight may not be well defined, and can be less than obtainedusing
16、 Test Methods D 4253.1.6 The values in inch-pound units are to be regarded as thestandard. The values stated in SI units are provided forinformation only.1.6.1 In the engineering profession it is customary practiceto use, interchangeably, units representing both mass and force,unless dynamic calcula
17、tions (F=Ma) are involved. Thisimplicitly combines two separate systems of units, that is, theabsolute system and the gravimetric system. It is scientificallyundesirable to combine the use of two separate systems withina single standard. This test method has been written usinginch-pound units (gravi
18、metric system) where the pound (lbf)represents a unit of force. The use of mass (lbm) is forconvenience of units and is not intended to convey the use isscientifically correct. Conversions are given in the SI system inaccordance with IEEE/ASTM SI 10. The use of balances orscales recording pounds of
19、mass (lbm), or the recording ofdensity in lbm/ft3should not be regarded as nonconformancewith this standard.1.7 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-priate safety
20、and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:C 127 Test Method for Specific Gravity and Absorption ofCoarse Aggregate2C 136 Test Method for Sieve Analysis of Fine and CoarseAggregates2D 422 Test Method for Part
21、icle-Size Analysis of Soils3D 653 Terminology Relating to Soil, Rock, and ContainedFluids3D 698 Test Method for Laboratory Compaction Character-istics of Soil Using Standard Effort 12,400 ft-lbf/ft3(600kN-mJ/m3)3D 854 Test Method for Specific Gravity of Soils3D 2168 Test Methods for Calibration of L
22、aboratoryMechanical-Rammer Soil Compactors3D 2216 Test Method for Laboratory Determination of Water(Moisture) Content of Soil and Rock by Mass3D 2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)3D 2488 Practice for Description and Identification o
23、f Soils(Visual-Manual Procedure)3D 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and Construction3D 4220 Practices for Preserving and Transporting SoilSamples3D 4253 Test Methods for Maximum Index Density of
24、SoilsUsing a Vibratory Table3D 4718 Practice for Correction of Unit Weight and WaterContent for Soils Containing Oversize Particles3D 4753 Specification for Evaluating, Selecting and Speci-fying Balances and Scales For Use in Soil, Rock, andConstruction MaterialsTesting3D 4914 Test Methods for Densi
25、ty of Soil and Rock in Placeby the Sand Replacement Method in a Test Pit3D 5030 Test Method for Density of Soil and Rock in Placeby the Water Replacement Method in a Test Pit4E1 Specification for ASTM Thermometers5E11 Specification for Wire-Cloth Sieves for Testing Pur-poses5E 319 Practice for the E
26、valuation of Single-Pan MechanicalBalances5IEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI): The Modern Metric System3. Terminology3.1 DefinitionsSee Terminology D 653 for general defini-tions.3.2 Definitions of Terms Specific to This Standard:3.2.1 modified effortthe term f
27、or the 56 000 ft-lbf/ft3(2700 kN-m/m3) compactive effort applied by the equipmentand methods of this test.3.2.2 modified maximum dry unit weight, gdmax(lbf/ft3(kN/m3)the maximum value defined by the compaction curvefor a compaction test using modified effort.3.2.3 modified optimum water content, wo(
28、%)the watercontent at which the soil can be compacted to the maximumdry unit weight using modified compactive effort.3.2.4 oversize fraction (coarse fraction), Pc(%)the por-tion of total sample not used in performing the compaction test;it may be the portion of total sample retained on the No. 4(4.7
29、5-mm),38-in. (9.5-mm), or34-in. (19.0-mm) sieve.3.2.5 test fraction (finer fraction), PF(%)the portion ofthe total sample used in performing the compaction test; it maybe fraction passing the No. 4 (4.75-mm) sieve in Method A,minus38-in. (9.5-mm) sieve in Method B, or minus34-in.(19.0-mm) sieve in M
30、ethod C.4. Summary of Test Method4.1 A soil at a selected water content is placed in five layersinto a mold of given dimensions, with each layer compacted by25 or 56 blows of a 10-lbf (44.5-N) rammer dropped from adistance of 18-in. (457-mm), subjecting the soil to a totalcompactive effort of about
31、56 000 ftlbf/ft3(2700 kN-m/m3).The resulting dry unit weight is determined. The procedure isrepeated for a sufficient number of water contents to establisha relationship between the dry unit weight and the watercontent for the soil. This data, when plotted, represent acurvilinear relationship known
32、as the compaction curve. Thevalues of optimum water content and modified maximum dryunit weight are determined from the compaction curve.2Annual Book of ASTM Standards, Vol 04.02.3Annual Book of ASTM Standards, Vol 04.08.4Annual Book of ASTM Standards, Vol 04.09.5Annual Book of ASTM Standards, Vol 1
33、4.02.D155702e125. Significance and Use5.1 Soil placed as engineering fill (embankments, founda-tion pads, road bases) is compacted to a dense state to obtainsatisfactory engineering properties such as, shear strength,compressibility, or permeability. Also, foundation soils areoften compacted to impr
34、ove their engineering properties.Laboratory compaction tests provide the basis for determiningthe percent compaction and water content needed to achievethe required engineering properties, and for controlling con-struction to assure that the required compaction and watercontents are achieved.5.2 Dur
35、ing design of an engineered fill, shear, consolidation,permeability, or other tests require preparation of test speci-mens by compacting at some water content to some unitweight. It is common practice to first determine the optimumwater content (wo) and maximum dry unit weight (gdmax)bymeans of a co
36、mpaction test. Test specimens are compacted ata selected water content (w), either wet or dry of optimum (wo)or at optimum (wo), and at a selected dry unit weight related toa percentage of maximum dry unit weight (gdmax). Theselection of water content (w), either wet or dry of optimum(wo) or at opti
37、mum (wo) and the dry unit weight (gdmax) may bebased on past experience, or a range of values may beinvestigated to determine the necessary percent of compaction.5.3 Experience indicates that the methods outlined in 5.2 orthe construction control aspects discussed in 5.1 are extremelydifficult to im
38、plement or yield erroneous results when dealingwith some soils. The following subsections describe typicalproblem soils, the problems encountered when dealing withsuch soils and possible solutions for these problems.5.3.1 Oversize FractionSoils containing more than 30 %oversize fraction (material re
39、tained on the34-in. (19-mm)sieve) are a problem. For such soils, there is no ASTM testmethod to control their compaction and very few laboratoriesare equipped to determine the laboratory maximum unit weight(density) of such soils (USDI Bureau of Reclamation, Denver,CO and U.S. Army Corps of Engineer
40、s, Vicksburg, MS).Although Test Methods D 4914 and D 5030 determine the“field” dry unit weight of such soils, they are difficult andexpensive to perform.5.3.1.1 One method to design and control the compaction ofsuch soils is to use a test fill to determine the required degreeof compaction and the me
41、thod to obtain that compaction. Thenuse a method specification to control the compaction. Compo-nents of a method specification typically contain the type andsize of compaction equipment to use, the lift thickness, andnumber of passes.NOTE 5Success in executing the compaction control of an earthwork
42、project, especially when a method specification is used, is highlydependent upon the quality and experience of the “contractor” and“inspector”.5.3.1.2 Another method is to apply the use of densitycorrection factors developed by the USDI Bureau of Reclama-tion (1,2)6and U.S. Corps of Engineers (3). T
43、hese correctionfactors may be applied for soils containing up to about 50 to70 % oversize fraction. Both agencies use a different term forthese density correction factors. The USDI Bureau of Recla-mation uses D ratio (or D VALUE), while the U.S. Corps ofEngineers uses Density Interference Coefficien
44、t (Ic).5.3.1.3 The use of the replacement technique (Test MethodD 155778, Method D), in which the oversize fraction isreplaced with a finer fraction, is inappropriate to determine themaximum dry unit weight, gdmax, of soils containing oversizefractions (3).5.3.2 DegradationSoils containing particles
45、 that degradeduring compaction are a problem, especially when moredegradation occurs during laboratory compaction than fieldcompaction, the typical case. Degradation typically occursduring the compaction of a granular-residual soil or aggregate.When degradation occurs, the maximum dry-unit weight in
46、-creases (4) so that the resulting laboratory maximum value isnot representative of field conditions. Often, in these cases, themaximum dry unit weight is impossible to achieve in the field.5.3.2.1 Again for soils subject to degradation, the use of testfills and method specifications may help. Use o
47、f replacementtechniques is not correct.5.3.3 Gap GradedGap-graded soils (soils containingmany large particles with limited small particles) are a problembecause the compacted soil will have larger voids than usual.To handle these large voids, standard test methods (laboratoryor field) typically have
48、 to be modified using engineeringjudgement.NOTE 6The 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 capab
49、le of competentand objective testing/sampling/inspection/etc. Users of this standard arecautioned that compliance with Practice D 3740 does not in itself assurereliable results. Reliable results depend on many factors; Practice D 3740provides a means of evaluating some of those factors.6. Apparatus6.1 Mold AssemblyThe molds shall be cylindrical inshape, made of rigid metal and be within the capacity anddimensions indicated in 6.1.1 or 6.1.2 and Fig. 1 and Fig. 2.The walls of the mold may be solid, split, or tapered. The“split” typ
