1、Designation: D2844 071D2844/D2844M 13Standard Test Method forResistance R-Value and Expansion Pressure of CompactedSoils1This standard is issued under the fixed designation D2844;D2844/D2844M; the number immediately following the designation indicatesthe year of original adoption or, in the case of
2、revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1 NOTEAdded research report information to Section 12 editorially in September 2010.1. Scope*1.1 This test m
3、ethod covers the procedure for testing both treated and untreated laboratory compacted soils or aggregates withthe stabilometer and expansion pressure devices to obtain results indicative of performance when placed in the base, subbase, orsubgrade of a road subjected to traffic.1.2 UnitsThe values s
4、tated in either SI units or inch-pound units presented in brackets are to be regarded as the separatelyas standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independentlyof the other. Combining values from the two systems may result in non-c
5、onformance with the standard. However, use of equipmentmanufactured to be readable in inch-pound units only should not be considered as non-conformance to the test method. Manystabilometers and expansion pressure devices are manufactured to be readable in inch-pound units only.1.3 All observed and c
6、alculated values shall conform to the guidelines for significant digits and rounding established in PracticeD6026.1.3.1 For purposes of comparing measured or calculated value(s) with specified limits, the measured or calculated value(s) shallbe rounded to the nearest decimal or significant digits in
7、 the specified limits.1.3.2 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industrystandard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do notconsider materi
8、al variation, purpose for obtaining the data, special purpose studies, or any considerations for the users objectives;and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations.It is beyond the scope of this standard to consider s
9、ignificant digits used in analytical methods for engineering design.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the a
10、pplicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction MaterialsD653 Terminology Relating to Soil, Rock, and Contained FluidsD3740 Practice for Minimum Requirements for
11、Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used inEngineering Design and ConstructionD6026 Practice for Using Significant Digits in Geotechnical DataE4 Practices for Force Verification of Testing MachinesE11 Specification for Woven Wire Test Sieve Cloth and Test Sieves2.2 AASH
12、TO Documents:T 190 Test Method for Resistance R-Value and Expansion Pressure of Compacted Soils31 This test method is under the jurisdiction ofASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.08 on Special and ConstructionControl Tests.Current edition approved
13、 Feb. 1, 2007Jan. 1, 2013. Published March 2007February 2013. Originally approved in 1969. Last previous edition approved in 20012007 asD2844 01071. DOI: 10.1520/D2844-07E01.10.1520/D2844_D2844M-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service a
14、t serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American Association of State Highway and Transportation Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,http:/www.tra
15、nsportation.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users c
16、onsult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohock
17、en, PA 19428-2959. United States12.3 ASTM Adjuncts:4Exudation DeviceExpansion Pressure ApparatusStabilometer2.4 CALTRANS Standard:5California Test 103 Method of Test For Calibration of Expansion Pressure Devices3. Terminology3.1 For definitions of terms in this test method, refer to Terminology D653
18、.4. Significance and Use4.1 This test method is used to measure the potential strength of subgrade, subbase, and base course materials for use in roadand airfield pavements. The R-value is used by some agencies as criteria for acceptance of aggregates for base course andbituminous courses.4.2 The ex
19、pansion pressure testing has been used in conjunction with the R-value test to determine cover requirements(thickness) and construction controls to reduce pavement distortion from expansive subgrade soils.NOTE 1The quality of the result produced by this standard is dependent on the competence of the
20、 personnel performing it, and the suitability of theequipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objectivetesting/sampling/inspection/etc. Users of this test method are cautioned that compliance with Practice D3740
21、 does not in itself ensure reliable results.Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.5. ApparatusNOTE 2The inch-pound dimensions presented in brackets, found in this section are for equipment commonly available in the United States.
22、5.1 Kneading Compactor, capable of applying an average contact pressure of 24106 110 kPa (350350 6 16 psi) psi to thetamper foot shown in Fig. 1Fig. 1 and with provisions for maintaining this pressure during changes in sample height. The load-timetrace shall be free of “chatter” or evidence of impac
23、t-associated changes in slope. The rise time for application of foot pressure,in the range from 240 to 2070 kPa (3535 to 300 psi),psi, shall not be less than 0.07 nor more than 0.20 s.0.07 to 0.20 seconds.The dwell time, measured at 300 psi 2070 kPa 300 psi foot pressure, shall not be less than 0.15
24、 nor more than 0.45 s.0.15 to 0.45seconds. The pressure-release or removal time shall not be greater than 0.60 s.seconds.5.1.1 The compactor shall include a counter or timer for measuring the number of tamps applied to a specimen and a moldholder, for use in compacting specimens, that rotates equall
25、y between tamps to give 5 to 7 tamps per revolution of the mold. Theholder shall firmly restrain the mold during compaction. The base of the mold holder shall have a metal plate 100.8. (3 100.8 mm4 Copies of detailed drawings of the apparatus shown in Figs. 4 (1 drawing), 67 (4 drawings), 710 and 81
26、1 (7 drawings) are available at a nominal cost from ASTMInternational Headquarters. Request Adjunct Nos. ADJD284401,ADJD284402, and ADJD284403, respectively.5 Available from State of California Department of Transportation (CALTRANS), P.O. Box 942873, Sacramento, CA 94273-0001, http:/www.dot.ca.gov.
27、 Proving LeverAssembly detailed drawings are available here as well.FIG. 1 Tamper Shoe for Kneading CompactorD2844/D2844M 1323 3132 in. in mm) in diameter and 12.7 mm (0.5 in.) high 0.5 in. in height, to which is cemented a rubber disk having a diameterof 100.0 mm (33 1516 in.)in. and a heightthickn
28、ess of 3.2 mm. (mm 18 in).in. The plate shall be an integral part of the baseof the mold holder. The compactor shall also include a trough for feeding the sample into the mold in 20 increments (Fig. 2).Troughs with a semicircular cross section of 39 cm2 (66.0 in.32) in area and 50.8 cm (20 in.) long
29、 20 in. in length have provensatisfactory.5.2 Compression Testing Machine, with a minimum capacity of 45 kN(10 000 lbf )kN 10 000 lbf and satisfying therequirements of Practices E4.5.3 Mold, 101.6 6 0.05 mm (44.0 6 0.002 in.)in. inside diameter by 127 6 0.20 mm (55.0 6 0.008 in.)in. high. (See Fig.3
30、 for surface roughness.)5.4 Rubber Disks, 100 mm (33 1516 in. ) in. in diameter by 3 mm (18 in.)in. thick and having a durometer hardness of 606 15.5.5 Metal Follower, solid-walled, metal specimen follower 100.33 6 0.13 mm (3.953.95 6 0.005 in. ) in. in outside diameterby 127 mm (5 in.)5.0 in. long.
31、5.6 Exudation Indicator Device, as shown in Fig. 4.4 and Fig. 5.5.7 Phosphor Bronze Disk, as shown in Fig. 56.5.8 Filter Paper, 100 mm 4.0 in. in diameter and .150.15 mm (0.006 in.) thick, 0.006 in. thick, with a smooth surface,medium filtering speed, medium retention.5.9 Filter Paper, 110 mm 4.3 in
32、. in diameter and .150.15 mm (0.006 in.) thick, 0.006 in. thick, with a creped surface,medium-fast filtering speed, and medium retention.5.10 Expansion-Pressure Device, with accessories as shown in Fig. 67. 4 There should be at least three of these devices for eachsample to be tested within a days t
33、ime.FIG. 2 Compactor with Sample Feed TroughD2844/D2844M 1335.11 Deflection Gage, with divisions of 0.002 mm (0.0001 in.)0.0001 in. and an allen wrench as shown in Fig. 67.5.12 Proving Lever Assembly, as shown in Fig. 8 and Fig. 9.55.13 Stabilometer, with accessories, as shown in Fig. 710 and Fig. 8
34、11.45.14 Standard Metal Specimen, 101.60 mm. (4 in)101.6 mm 4.0 in. in outside diameter by 152.2 mm (6 in.)6.0 in. high asshown in Fig. 811.5.15 Balance, 5000-g capacity, accurate and readable to 1 g.5.16 Sieves, 25.0 mm (1 in.),1 in., 19.0 mm (34 in.)in. and 4.75 mm (No. 4)No. 4 conforming to the r
35、equirements ofSpecification E11.5.17 Miscellaneous Equipment, including mixing pans, spoons, spatulas, and gallon cans with close-fitting lids.6. Soil Preparation6.1 Remove any coatings from coarse aggregate and break clay lumps to pass the 4.75-mm (No. 4)No. 4 sieve.6.2 Adjust the soil graduation w
36、hen some of the gradation when material is retained on the 19.0-mm (34-in.)-in. sieve. When75 %75 % or more passes the 19.0mm (19.0-mm 34-in).-in. sieve, use that part of the sample passing the 19.0mm (19.0-mm34-in.)-in. sieve. If less than 75 %75 % of the sample passes the 1-in. sieve 25.0-mm 1-in.
37、 sieve, use that part of the samplepassing the 25.0-mm (1-in. ) sieve.1-in. sieve. See Table 1 for a sample calculation.NOTE 1Inside roughness is obtained by smooth machining inside to required diameter of 101.6 6 0.05 mm (4.0004.000 6 0.002 in.)in. followedon final operation with a boring tool bit
38、ground to a 90 point with sharp point ground flat measuring 0.025 to 0.075 mm (0.0010.001 to 0.003 in.)in.across. Depth of cut is 0.050mm (0.002 in.) with 0.25mm (0.010 in.) 0.050 mm 0.002 in. with 0.25 mm 0.010 in. feed using sulfur-based oil coolant.FIG. 3 MoldD2844/D2844M 134FIG. 4 Circular Exuda
39、tion-Indicator DeviceFIG. 5 Linear Exudation-Indicator DeviceD2844/D2844M 1357. Preparation of Soil Specimens7.1 Thoroughly mix four approximately 1200-g 2.7-lb samples of soil with the amount of water estimated to equal one halfto two thirds of the water required to produce saturation as defined in
40、 7.3 and 7.4. Place the samples in covered containers andallow them to stand overnight. Just prior to compaction, mix the samples with the final amount of water required to producesaturation. The first sample is used as a pilot specimen to assist in determining the final amount of water required.7.2
41、 Weigh out enough material to fabricate a compacted sample 101.6 mm (4 in.)4.0 in. in diameter by 63 mm (2.5 in.)2.5in. high. Compacted specimens having heights from 62 to 65 mm (2.452.45 to 2.55 in.)in. are acceptable. Compact the soil intothe mold by means of the kneading compactor as follows: Pla
42、ce the mold in the mold holder which has a rubber disk, 100 mm(3 over the mold holder. 1516 in.) in diameter and 3 mm (18 in.) thick, cemented to the plate. Adjust the mold for approximately3-mm (18-in. ) -in. clearance between the lower edge of the mold and base of the mold holder. A metal angle br
43、acket of 3-mm18-in. thickness and approximately 37.5 mm 112 in. length placed on the base of the mold holder have proven satisfactory.Alternately, tighten the set screw, if available, on the mold holder. Spread the sample along the length of the trough. With thecompactor-foot pressure set at 1720 6
44、170 kPa (250250 6 25 psi),psi, feed 7675 mm (3 in.)3.0 in. of the soil from the troughinto the mold. Redistribute the sample remaining in trough as needed to feed the balance of the soil into the mold in 20 equalincrements with one application of the ram after each increment. Allow 10 additional tam
45、ps to level the soil, then place a rubberdisk on top of the specimen. Remove the shim from under the mold or loosen the set screw. Apply 100 additional tamps with afoot pressure of 2410 kPa (350 psi).350 psi. Stop compacting the soil at any time before 100 tamps if water appears around thebottom of
46、the mold.NOTE 3Use lower compaction pressures when necessary to limit penetration of the ram into the soil to not greater than 6 mm (14 in.).in.7.3 Remove the mold containing the compacted specimen from the compactor. Level the tamped surface by hand tamping witha 38-mm (1.5-in.)1.5-in. diameter rod
47、. Place a phosphor-bronze disk on the tamped surface of the soil and place a 100-mm filterpaper on top of the bronze disk. Invert the mold and place it on the exudation device so that the filter paper is on the bottom. Placethe solid walled, metal specimen follower into the mold. Using the compressi
48、on testing machine, apply a uniformly increasingpressure to the soil at the rate of 8900 N(2000 N 2000 lbf )/min./min. Water should be exuded from the soil at 2070 kPa (300psi)300 psi as evidence that enough moisture is present to produce saturation. Stop the loading and record the exudation pressur
49、eto the nearest 10 kPa (1 psi)1 psi when either five of the six outerindicator lights on the exudation pressureindicator device arelighted or three outerindicator lights are lighted and free water is visible around the bottom of the mold. Do not exceed a exudationpressure of 5520 kPa (800 psi).800 psi.7.4 Mold at least two more specimens with different amounts of moisture so that a range of exudation pressures from 690 to5520 kPa (10010
