1、Designation: D4943 18Standard Test Method forShrinkage Factors of Cohesive Soils by the WaterSubmersion Method1This standard is issued under the fixed designation D4943; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast 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 This test method covers the procedure for determiningthe shrinkage factors of cohesive soils, using the water sub-mers
3、ion technique, whereby the volume of a dried soil pat isdetermined while suspended in a water bath.1.2 The data obtained following this test method are alsoused to determine the shrinkage ratio, volumetric shrinkage,and linear shrinkage of the soil.1.3 This test method is applicable only for cohesiv
4、e soils.1.4 Since this test method is performed only on that portionof a soil which passes the 425-m (No. 40) sieve, the relativeconsistency of the tested portion of the soil to the properties ofthe sample as a whole must be considered when evaluating theentire soil sample.1.5 All recorded and calcu
5、lated values shall conform to theguide for significant digits and rounding established in PracticeD6026.1.5.1 The procedures, used to specify how data arecollected/recorded and calculated in this standard, are regardedas the industry standard. In addition, they are representative ofthe significant d
6、igits that should generally be retained. Theprocedures used do not consider material variation, purpose forobtaining the data, special purpose studies, or any consider-ations for the users objectives; and it is common practice toincrease or reduce significant digits of reported data to becommensurat
7、e with these considerations. It is beyond the scopeof this standard to consider significant digits used in analysismethods for engineering design.1.6 UnitsThe values stated in SI units are to be regardedas standard except the sieve designations are shown using thealternative sieve designation in par
8、entheses. No other units ofmeasurement are included in 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, health, and environmental practices an
9、d deter-mine the applicability of regulatory limitations prior to use.For specific safety hazards, see Section 8.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of
10、 International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC702 Practice for Red
11、ucing Samples ofAggregate to TestingSizeD75 Practice for Sampling AggregatesD420 Guide for Site Characterization for Engineering De-sign and Construction PurposesD653 Terminology Relating to Soil, Rock, and ContainedFluidsD854 Test Methods for Specific Gravity of Soil Solids byWater PycnometerD3740
12、Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4318 Test Methods for Liquid Limit, Plastic Limit, andPlasticity Index of SoilsD4753 Guide for Evaluating, Selecting, and Specifying Bal-ances and Standar
13、d Masses for Use in Soil, Rock, andConstruction Materials TestingD6026 Practice for Using Significant Digits in GeotechnicalDataE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision LiquidsE11 Specification for Woven Wire Test Sieve Cloth and TestSieves1This test metho
14、d 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 June 1, 2018. Published July 2018. Originally approvedin 1989. Last previous edition approved i
15、n 2008 as D4943 08, which waswithdrawn April 2017 and reinstated in June 2018. DOI: 10.1520/D4943-18.2For 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 D
16、ocument Summary page onthe ASTM website.*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 developed in accordance with internationally recog
17、nized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13. Terminology3.1 Definitions:3.1.1 For definitions of common te
18、chnical terms found inthis standard, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 shrinkage factors of soilsdeterminations made on asoil pat consisting of the Shrinkage Limit, Shrinkage Ratio,Linear Shrinkage and Volumetric Shrinkage.3.2.1.1 shrinkage limitthe s
19、hrinkage limit is the watercontent of a soil where further loss of moisture will result in noadditional volume reduction.3.2.1.2 shrinkage ratiothe ratio in the change in soilvolume, expressed as a percentage of the dry volume, to thecorresponding change in water content above the shrinkagelimit, ex
20、pressed as a percentage of the mass of oven-dried soil.3.2.1.3 linear shrinkagethe decrease in one dimension ofa soil mass, expressed as a percentage of the originaldimension, when the water content is reduced from a givenvalue to the shrinkage limit.3.2.1.4 volumetric shrinkagethe decrease in volum
21、e, ex-pressed as a percentage of the soil mass when dried, of a soilmass when the water content is reduced from a given percent-age to the shrinkage limit.3.2.2 soil patthe intact dry or wetted soil specimenmolded in a shrinkage dish.4. Summary of Test Method4.1 A sample of fine-grained soil is thor
22、oughly mixed withdistilled or demineralized water to form a paste that is slightlywetter than the liquid limit consistency. This paste is used to filla small dish to form a soil pat. The initial water content of thewet soil pat is determined. The soil pat is slowly dried to aconstant mass. The chang
23、e in volume of the soil, due to drying,is determined using a water submersion technique. A thincoating of wax is used to prevent water absorption by the drysoil pat during submersion in the water. Then, the water contentloss to dry the soil to a constant volume is determined andsubtracted from the i
24、nitial water content to calculate theshrinkage limit. The changes in specimen volume and mass areused to compute the shrinkage factors of the soil.5. Significance and Use5.1 The shrinkage limit can be used to evaluate the shrink-age potential, crack development potential, and swell potentialof earth
25、work involving cohesive soils.5.2 The shrinkage limit, along with the liquid limit andplastic limit of soil, are often collectively referred to as theAtterberg limits in recognition of their formation by Swedishsoil scientist, A. Atterberg. These limits distinguish the bound-aries of the several con
26、sistency states of cohesive soils.NOTE 1The 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 comp
27、etentand 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
28、Balance or ScaleA balance or scale having a mini-mum capacity of 500 g and meeting the requirements ofSpecification D4753 for a balance of 0.01-g readability.6.2 Suspension Apparatus (optional)A device centered onthe balance, suitable for suspending the soil specimen in acontainer of water located i
29、n proximity to the balance or scale.6.3 Shrinkage DishA circular porcelain or monel metalmilk dish having a flat bottom about 40 to 45 mm in diameterand about 12 to 15 mm deep.6.4 Drying OvenAn oven, thermostatically controlled,preferably of the forced draft type, and capable of maintaininga uniform
30、 temperature of 110 6 5C throughout the dryingchamber.6.5 Humidity Enclosure (optional)Small closed containerlarge enough for shrinkage dishes and a small container ofwater used in dry climates to slow the initial rate of drying.6.6 Mortar and PestleMortar, iron or porcelain, withrubber tipped pestl
31、e.6.7 SpatulaA spatula or pill knife having a blade suffi-ciently long and wide enough for easy use when mixing andplacing the prepared soil in the shrinkage dish. A blade about100 mm long by 20 mm wide has been found to be acceptable.6.8 StraightedgeA stiff metal straightedge of convenientlength. T
32、he scraping edge shall be beveled if it is thicker than3 mm.6.9 Sieve425-m (No. 40) sieve conforming to the re-quirements of Specification E11.6.10 WaxMicrocrystalline or other suitable wax mixturewhich does not become brittle when dry and does not shrinkduring solidification. Sufficient quantity wh
33、en melted in thewax warmer to submerge the soil pat.NOTE 2A 50/50 mixture of paraffin wax and petroleum jelly by masshas been demonstrated to provide an adequate alternative.6.11 Sewing Thread or Fine Fishing LineFine sewingthread or fine fishing line to hold the specimen to dip into thewax and susp
34、end the specimen during the mass in waterdetermination.6.12 Water BathOf sufficient size (for example, 250 mLbeaker) to fully submerge the soil pat when determiningindicated mass in water.6.13 Wax WarmerWith sufficient temperature control toavoid overheating.6.14 Tongs or GlovesFor handling hot mate
35、rials.6.15 ThermometerA thermometer, capable of measuringin the room temperature range with 0.5C gradations andconforming to the requirements of Specification E2251.6.16 Glass or Clear Plastic Plate, about 80 by 80 mm, andabout 5 mm thick used for determining the volume of theshrinkage dish.D4943 18
36、26.17 Petroleum Based Lubricant, used to grease the shrink-age dish.6.18 Liquid Limit Device and Grooving Tool, as described inTest Method D4318.7. Reagents and Materials7.1 Purity of WaterWhere distilled water is referred to inthis test method, either distilled or demineralized water may beused.8.
37、Safety Hazards8.1 Wax melting equipment and hot wax may burn unpro-tected skin. Overheated wax may burst into flames; therefore,extreme care should be exercised when working with hot wax.Do not use an open flame device to heat wax.9. Sampling9.1 Obtain samples from any location that satisfies testin
38、gneeds. However, use Practices C702 and D75, as well as GuideD420, as guides for selecting and preserving samples fromvarious types of sampling operations.9.2 Where sampling operations have preserved the naturalstratification of a sample, keep the various strata separated andperform tests on the par
39、ticular stratum of interest with as littlecontamination as possible from other strata. Where a mixtureof materials will be used in construction, combine the variouscomponents in such proportions that the resultant samplerepresents the actual construction case.9.3 Where data from this test method are
40、 to be used forcorrelation with other laboratory or field test data, use the samematerial as used for these tests whenever possible.9.4 Obtain a representative portion of soil from the totalsample sufficient to provide 150 to 200 g of material passingthe 425-m (No. 40) sieve. Mix samples thoroughly
41、in a panwith a spatula or scoop and obtain a representative portionfrom the total mass by making one or more sweeps with ascoop through the mixed mass.10. Volume Determination and Standardization10.1 Determine the volume of each shrinkage dish used inaccordance with Annex A1. Since the dishes may ha
42、vedifferent volumes, each dish must be permanently identified.10.2 The specific gravity (or density) of the wax must beknown in advance to at least two significant digits. This canoften be obtained from the manufacturer, but shall be deter-mined in accordance with Annex A2. The specific gravity ofth
43、e wax shall be determined initially and each time the wax isreplenished.10.3 Equalize the water bath, testing apparatus, and thelaboratory environment to about room temperature whileperforming both the dish volume determinations and theindividual test measurement. Temperature differences, as largeas
44、 5C, will not adversely impact the shrinkage limit whenreported to the nearest whole number. A thermometer shall beused to verify that the water bath and water, used for the dishvolume determinations, are within 5C. Either distilled, de-ionized or tap water may be used for the water bath andshrinkag
45、e dish volume determination. However, the same typeof water shall be used for both purposes.11. Preparation of Test Specimen11.1 Prepare the test specimen in accordance with theprocedures outlined in Test Method D4318, using either thewet or dry preparation procedure. The water content of the soilsh
46、all be adjusted to a consistency that will require about tenblows of the liquid limit device to close the groove along adistance of 13 mm. Dependent upon the soil type, the amountof water required may exceed the liquid limit by as much as 10percent.12. Procedure12.1 Select a shrinkage dish and recor
47、d its identificationdesignation and its volume. The volume of the shrinkage dishis used as the volume of the wet soil pat and is determined byprocedures outlined in A1.3 and A1.4. Lightly grease the insideof the shrinkage dish.12.2 Determine and record the mass of the greased shrink-age dish.12.3 Pl
48、ace, in the center of the dish, an amount of theprepared soil equal to about one-third the volume of the dishand cause the soil to flow to the edges by tapping the dish ona firm surface, cushioned by several layers of blotting paper orsimilar material. Add an amount of soil approximately equal tothe
49、 first portion, and tap the dish until the soil is thoroughlycompacted and entrapped air has been brought to the surface.Add additional soil and continue the tapping until the dish iscompletely filled and excess soil flows over its edge. Strike offthe excess soil with a straightedge and level the soil with thetop edge of the shrinkage dish. Wipe off all soil adhering to theoutside of the dish.12.4 Determine and record the mass of the dish plus wet soilimmediately after leveling.12.5 Allow the soil pat to dry in air until the color of the patturns fr