1、Designation: D 7263 09Standard Test Methods forLaboratory Determination of Density (Unit Weight) of SoilSpecimens1This standard is issued under the fixed designation D 7263; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、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. Scope1.1 These test methods describe two ways of determiningthe total/moist and dry densities (unit weights) of intact,distu
3、rbed, remolded, and reconstituted (compacted) soil speci-mens. Density (unit weight) as used in this standard means thesame as “bulk density” of soil as defined by the Soil ScienceSociety of America. Intact specimens may be obtained fromthin-walled sampling tubes, block samples, or clods. Speci-mens
4、 that are remolded by dynamic or static compactionprocedures may also be measured by these methods. Thesemethods apply to soils that will retain their shape during themeasurement process and may also apply to other materialssuch as soil-cement, soil-lime, soil-bentonite or solidifiedsoil-bentonite-c
5、ement slurries. It is common for the density(unit weight) of specimens after removal from sampling tubesand compaction molds to be less than the value based on tubeor mold volumes, or of in-situ conditions. This is due to thespecimen swelling after removal of lateral pressures.1.1.1 Method A covers
6、the procedure for measuring thevolume of wax coated specimens by determining the quantityof water displaced.1.1.1.1 This method only applies to specimens in which thewax will not penetrate the outer surface of the specimen.1.1.2 Method B covers the procedure by means of the directmeasurement of the
7、dimensions and mass of a specimen,usually one of cylindrical shape. Intact and reconstituted/remolded specimens may be tested by this method in conjunc-tion with strength, permeability (air/water) and compressibilitydeterminations.1.2 The values stated in SI units are to be regarded as thestandard.
8、The values stated in inch-pound units are approxi-mate.1.3 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D 6026.1.3.1 The method used to specify how data are collected,calculated, or recorded in this standard is not direc
9、tly related tothe accuracy with which the data can be applied in design orother uses, or both. How one applies the results obtained usingthis standard is beyond its scope.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
10、 of the user of this standard 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:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 698 Test Methods for Laboratory Compac
11、tion Character-istics of Soil Using Standard Effort (12 400 ft-lbf/ft3(600kN-m/m3)D 854 Test Methods for Specific Gravity of Soil Solids byWater PycnometerD 1557 Test Methods for Laboratory Compaction Charac-teristics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3)D 1587 Practice for
12、 Thin-Walled Tube Sampling of Soilsfor Geotechnical PurposesD 2166 Test Method for Unconfined Compressive Strengthof Cohesive SoilD 2216 Test Methods for Laboratory Determination of Wa-ter (Moisture) Content of Soil and Rock by MassD 2487 Practice for Classification of Soils for EngineeringPurposes
13、(Unified Soil Classification System)D 2488 Practice for Description and Identification of Soils(Visual-Manual Procedure)D 3550 Practice for Thick Wall, Ring-Lined, Split Barrel,Drive Sampling of SoilsD 3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil an
14、d Rock asUsed in Engineering Design and ConstructionD 4220 Practices for Preserving and Transporting SoilSamplesD 4318 Test Methods for Liquid Limit, Plastic Limit, and1These test methods are under the jurisdiction ofASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommitte
15、e D18.03 on Texture,Plasticity and Density Characteristics of Soils.Current edition approved March 15, 2009. Published April 2009.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informat
16、ion, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Plasticity Index of SoilsD 4753 Guide for Evaluating, Selecting, and SpecifyingBalances and Standard Masses for Use
17、in Soil, Rock, andConstruction Materials TestingD 6026 Practice for Using Significant Digits in Geotechni-cal DataE 2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision Liquids2.2 Other Reference:Soil Science Society of America Glossary of Soil ScienceTerms33. Terminol
18、ogy3.1 Refer to Terminology D 653 for standard definitions ofterms.4. Significance and Use4.1 Dry density, as defined as “density of soil or rock” inTerminology D 653 and “bulk density” by soil scientists, canbe used to convert the water fraction of soil from a mass basisto a volume basis and vise-v
19、ersa. When particle density, that is,specific gravity (Test Methods D 854) is also known, drydensity can be used to calculate porosity and void ratio (seeAppendix X1). Dry density measurements are also useful fordetermining degree of soil compaction. Since moisture contentis variable, moist soil den
20、sity provides little useful informationexcept to estimate the weight of soil per unit volume, forexample, pounds per cubic yard, at the time of sampling. Sincesoil volume shrinks with drying of swelling soils, bulk densitywill vary with moisture content. Hence, the water content ofthe soil should be
21、 determined at the time of sampling.4.2 Densities (unit weights) of remolded/reconstitutedspecimens are commonly used to evaluate the degree ofcompaction of earthen fills, embankments, etc. Dry densityvalues are usually used in conjunction with compaction curvevalues (Test Methods D 698 and D 1557).
22、4.3 Density (unit weight) is one of the key components indetermining the mass composition/phase relations of soil, seeAppendix X1.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
23、used. Agencies that meet thecriteria of Practice D 3740 are generally considered capable 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 several f
24、actors; PracticeD 3740 provides a means of evaluating some of these factors.5. Apparatus5.1 For Method A the following apparatus are required:5.1.1 BalanceAll balances must meet the requirements ofSpecification D 4753 and this section. A Class GP1 balance of0.01 g readability is required for specime
25、ns having a mass upto 200 grams and a Class GP2 balance of 0.1 g readability isrequired for specimens having a mass over 200 grams. Formethod A, the balance must be capable of measuring the massof the specimen suspended in water. This is usually accom-plished by a weighing hook built into the balanc
26、e for thatpurpose, or a yoke assemblage is placed upon the pan whichsuspends a thin, non-absorbent string or wire, that is, a nylonline, etc., below the balance into the water reservoir.5.1.2 Drying OvenA thermostatically controlled, prefer-ably of the forced-draft type, capable of maintaining a uni
27、formtemperature of 110 6 5C throughout the drying chamber.5.1.3 WaxNon-shrinking, paraffin and/or microcrystallinewax that has a known and constant density, rr, to foursignificant figures and that does not change after repeatedmelting and cooling cycles.NOTE 2The waxes generally used are commerciall
28、y available andhave density values in the range of 0.87 to 0.91 g/cm3or Mg/m3.5.1.4 Wax-Melting ContainerUsed to melt the wax, butshould not allow the wax to overheat.Acontainer heated by hotwater, preferably thermostatically controlled, is satisfactory.The wax should be heated to only slightly abov
29、e the meltingpoint to avoid flashing of the wax vapors and to permit quicklyforming a uniform surface coating of wax. WarningVaporsgiven off by molten wax ignite spontaneously above 205C(400F) and should not be allowed to come in contact with theheating element or open flame.5.1.5 Wire BasketA wire
30、basket of 3.35 mm or finer meshof approximately equal width and height of sufficient size tocontain the specimen. The basket shall be constructed toprevent trapping air when it is submerged. The basket issuspended from the balance by a fine thread or string.Ahairnetmay also be used in lieu of the ba
31、sket for smaller soilspecimens.5.1.6 ContainerA container or tank of sufficient size tocontain the submerged basket and specimen.5.1.7 Specimen ContainerA corrosion-resistant containerof sufficient size to contain the specimen for water contentdetermination.5.1.8 ThermometerCapable of measuring the
32、temperaturerange within which the test is being performed graduated in a0.1 degree C division scale and meeting the requirements ofSpecification E 2251.5.1.9 Container Handling ApparatusGloves or suitableholder for moving and handling hot containers.5.1.10 MiscellaneousPaintbrush, trimming tools, sp
33、eci-men containers, and data sheets provided as required.5.2 For Method B the following apparatus are needed:5.2.1 BalanceSee 5.1.1.5.2.2 Drying OvenSee 5.1.2.5.2.3 Specimen-Size Measurement DevicesDevices usedto determine the height and width or diameter of the specimenshall measure the respective
34、dimensions to four significantdigits and shall be constructed so that their use will not indentor penetrate into the specimen.NOTE 3Circumferential measuring tapes are recommended over cali-pers for measuring the diameter of cylindrical specimens.5.2.4 Apparatus for Preparing Reconstituted or Remold
35、edSpecimens (Optional)Such apparatus is only required ifthese types of specimens are being tested.3Available online: www.soils.org/sssagloss/index.php.D72630925.2.5 Miscellaneous ApparatusSpecimen trimming andcarving tools including a wire saw, steel straightedge, miterbox and vertical trimming lath
36、e, specimen containers, and datasheets shall be provided as required.6. Samples and Test Specimens6.1 SamplesIntact samples shall be preserved and trans-ported in accordance with Practice D 4220 Groups C and Dsoil. Compacted or remolded specimens shall be preserved inaccordance with Practice D 4220
37、Group B soil. Maintain thesamples that are stored prior to testing in non-corrodibleairtight containers at a temperature between approximately 3and 30C and in an area that prevents direct contact withsunlight.6.2 SpecimensSpecimens for testing shall be sufficientlycohesive and firm to maintain shape
38、 during the measuringprocedure if Method A is used, see 1.1.1.1. Specimens shallhave a minimum dimension of 30 mm (1.3 in.) and the largestparticle contained within the test specimen shall be smallerthan one-tenth of the specimens smallest dimension. Forspecimens having a dimension of 72 mm (2.8 in.
39、) or larger, thelargest particle size shall be smaller than one-sixth of thespecimens smallest dimension. If, after completion of a test onan intact specimen, visual observations indicate that largerparticles than permitted are present, indicate this information inthe remarks section of the report o
40、f test data.7. Procedure7.1 Record all identifying information for the specimen,such as project, boring number, depth, sample type (that is,tube, trimmed, etc.), visual soil classification (PracticeD 2488), or other pertinent data.7.2 Method AWater Displacement:7.2.1 Determine, if not previously est
41、ablished, the densityof the wax to be used to four significant digits (see 5.1.3).7.2.2 Prepare specimens in an environment that minimizesany changes in water content. For some soils, changes in watercontent are minimized by trimming specimens in a controlledenvironment, such as a controlled high-hu
42、midity room/enclosure.7.2.3 If required, cut a specimen meeting the size require-ments given in 6.2 from the sample to be tested. If required,trim the specimen to a fairly regular shape. Re-entrant anglesshould be avoided, and any cavities formed by large particlesbeing pulled out should be patched
43、carefully with materialfrom the trimmings. Handle specimens carefully to minimizedisturbance, change in shape, or change in water content.Typically, for most samples, changes in water content areminimized by trimming specimens, in a controlled environ-ment, such as a controlled high-humidity room/en
44、closure.7.2.4 Determine and record the moist mass of the soilspecimen (Mt) to four significant figures in g or kg.7.2.5 Cover the specimen with a thin coat of melted wax,either with a paintbrush or by dipping the specimen in acontainer of melted wax. Apply a second coat of wax after thefirst coat ha
45、s hardened. The wax should be sufficiently warm toflow when brushed on the specimen, yet it should not be so hotthat it dries the soil.NOTE 4If overheated wax comes in contact with the soil specimen, itmay cause the moisture to vaporize and form air bubbles under the wax.Bubbles may be trimmed out a
46、nd filled with wax.7.2.6 Determine and record the mass of the wax-coatedspecimen in air (MC) to four significant figures in g or kg.7.2.7 Determine and record the submerged mass of thewax-coated specimen (Msub) to four significant digits in g orkg. This is done by placing the specimen in a wire bask
47、ethooked onto a balance and immersing the basket and specimenin a container of water. In order to directly measure thesubmerged mass of the wet soil and wax, the balance must havebeen previously balanced (tared to zero) with the wire basketcompletely submerged in the container of water. Make suretha
48、t the specimen and basket is fully submerged, and that thebasket is not touching the sides or bottom of the container.7.2.8 Record the temperature of the water to 0.1 degrees C.NOTE 5Maintain water bath temperature and submerged basket depththe same as when calibrated or zeroed.7.2.9 Remove the wax
49、from the specimen. It can be peeledoff after a break is made in the wax surface.7.2.10 Determine the water content to the nearest 0.1percent in accordance with Method D 2216.NOTE 6The water content may be determined from an adjacent pieceof soil or from trimmings if appropriate, for example, if the wax becomesdifficult to remove from the specimen. Note in the report if water contentis not from the specimen itself.7.3 Method BDirect Measurement:7.3.1 Intact SpecimensPrepare intact specimens fromlarge block samples or from samples secured in accordance
