ASTM D6035-2002 Standard Test Method for Determining the Effect of Freeze-Thaw on Hydraulic Conductivity of Compacted or Undisturbed Soil Specimens Using a Flexible Wall Permeamete.pdf

1、Designation: D 6035 02Standard Test Method forDetermining the Effect of Freeze-Thaw on HydraulicConductivity of Compacted or Undisturbed Soil SpecimensUsing a Flexible Wall Permeameter1This standard is issued under the fixed designation D 6035; the number immediately following the designation indica

2、tes the 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. Scope *1.1 This test method covers laboratory measur

3、ement of theeffect of freeze-thaw on the hydraulic conductivity of com-pacted or undisturbed soil specimens (using Test MethodD 5084 and a flexible wall permeameter to determine hydraulicconductivity). This test method does not provide steps toperform sampling of, or testing on, in situ soils that h

4、avealready been subjected to freeze-thaw conditions.1.2 This test method may be used with undisturbed speci-mens (block or thin-walled) or laboratory compacted speci-mens and shall be used for soils that have an initial hydraulicconductivity less than or equal to 1E-5 m/s (1E-3 cm/s) (Note1).NOTE 1T

5、he maximum initial hydraulic conductivity is given as 1 E-3cm/s. This should also apply to the final hydraulic conductivity. It isexpected that if the initial hydraulic conductivity is 1 E-3 cm/s, than thefinal hydraulic conductivity will not change (increase) significantly (thatis, greater than 1 E

6、-3 cm/s).1.3 Soil specimens tested using this test method can besubjected to three-dimensional freeze-thaw (herein referred toas 3-d) or one-dimensional freeze-thaw (herein referred to as1-d). (For a discussion of one-dimensional freezing versusthree-dimensional freezing, refer to Zimmie2or Othman.3

7、)1.4 Soil specimens tested using this test method can betested in a closed system (that is, no access to an externalsupply of water during freezing) or an open system.1.5 The values stated in SI units are to be regarded as thestandard, unless other units are specifically given. By tradition,it is U.

8、S. practice to report hydraulic conductivity in centime-tres per second, although the common SI units for hydraulicconductivity are metres per second. The values are to becalculated and reported in accordance with Practice D 6026.1.6 This standard does not purport to address all of thesafety concern

9、s, if any, associated with its use. It is theresponsibility 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:D 653 Terminology Relating to Soil, Rock, a

10、nd ContainedFluids4D 1587 Practice for Thin-Walled Tube Geotechnical Sam-pling of Soils4D 2113 Practice for Diamond Core Drilling for Site Inves-tigation4D 2216 Test Method for Laboratory Determination of Water(Moisture) Content of Soil and Rock4D 3740 Practice for Minimum Requirements for AgenciesE

11、ngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and Construction4D 4220 Practice for Preserving and Transporting SoilSamples4D 4753 Specification for Evaluating, Selecting, and Speci-fying Balances and Scales for Use in Testing Soil, Rock,and Related Constructio

12、n Materials4D 5084 Test Method for Measurement of Hydraulic Con-ductivity of Saturated Porous Materials Using a FlexibleWall Permeameter4D 6026 Practice for Using Significant Digits in Geotechni-cal Data51This test method is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the dir

13、ect responsibility of Subcommittee D18.19 on Frozen Soil andRock.Current edition approved July 10, 2002. Published September 2002. Originallypublished as D 603596. Last previous edition D 603596.2Zimmie, T. F., and La Plante, C., “The Effect of Freeze/Thaw Cycles on thePermeability of a Fine-Grained

14、 Soil,” Hazardous and Industrial Wastes, Proceed-ings of the Twenty-Second Mid-Atlantic Industrial Waste Conference, Joseph P.Martin, Shi-Chieh Cheng, and Mary Ann Susavidge, eds., Drexel University, 1990,pp. 580593.3Othman, M. A., Benson, C. H., Chamberlain, E. J., and Zimmie, T. F.,“Laboratory Tes

15、ting to Evaluate Changes in Hydraulic Conductivity of CompactedClays Caused by Freeze-Thaw: State-of-the-Art,” Hydraulic Conductivity andWaste Contaminant Transport in Soils, ASTM STP 1142, David E. Daniel, andStephen J. Trautwein, eds., American Society for Testing and Materials, Consho-hocken, PA,

16、 pp. 227254.4Annual Book of ASTM Standards, Vol 04.08.5Annual Book of ASTM Standards, Vol 04.09.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 145 Specification for

17、 Gravity-Convection and Forced-Ventilation Ovens63. Terminology3.1 Refer to Terminology D 653 for standard definitions ofterms.3.2 Definitions of Terms Specific to This Standard:3.2.1 freeze-thaw cycle, na loop from room temperatureto the ambient temperature of the freezing cabinet, and back toroom

18、temperature.3.2.2 freezing, closed system, nfreezing that occurs underconditions that preclude the gain or loss of any water in thesystem.3.2.3 freezing, open system, nfreezing that occurs underconditions that allow the gain or loss of water in the system bymovement of pore water from or to an exter

19、nal source togrowing ice lenses.3.2.4 hydraulic conductivity, k, nthe rate of discharge ofwater under laminar flow conditions through a unit cross-sectional area of a porous medium under a unit hydraulicgradient and standard temperature conditions (20C).4. Significance and Use4.1 This test method id

20、entifies the changes in hydraulicconductivity as a result of freeze-thaw on natural soils only.4.2 In using this test method the user shall both conduct thetests and provide the supervision required in accordance withPractice D 3740. Test values shall be calculated and recordedin accordance with Pra

21、ctice D 60264.3 It is the users responsibility when using this test methodto determine the appropriate moisture content of thelaboratory-compacted specimens (that is, dry, wet, or at opti-mum moisture content) (Note 2).NOTE 2It is common practice to construct clay liners and covers atoptimum or grea

22、ter than optimum moisture content. Specimens com-pacted dry of optimum moisture content typically do not contain largerpore sizes as a result of freeze-thaw because the effects of freeze-thaw areminimized by the lack of water in the sample. Therefore, the effect offreeze-thaw on the hydraulic conduc

23、tivity is minimal, or the hydraulicconductivity may increase slightly.3,74.4 The requestor must provide information regarding theeffective stresses to be applied during testing, especially fordetermining the final hydraulic conductivity. Using high effec-tive stresses (that is, 35 kPa (5 psi) as all

24、owed by Test MethodD 5084) can decrease an already increased hydraulic conduc-tivity resulting in lower final hydraulic conductivity values.The long-term effect of freeze-thaw on the hydraulic conduc-tivity of compacted soils is unknown. The increased hydraulicconductivity caused by freeze-thaw may

25、be temporary. Forexample, the overburden pressure imparted by the waste placedon a soil liner in a landfill after being subjected to freeze-thawmay reduce the size of the cracks and pores that cause theincrease in hydraulic conductivity. It is not known if thepressure would overcome the macroscopica

26、lly increased hy-draulic conductivity sufficiently to return the soil to its originalhydraulic conductivity (prior to freeze-thaw). For cases such aslandfill covers, where the overburden pressure is low, theincrease in hydraulic conductivity due to freeze-thaw willlikely be permanent. Thus, the requ

27、estor must take the appli-cation of the test method into account when establishing theeffective stress.4.5 The specimen shall be frozen to 15C unless therequestor specifically dictates otherwise. It has been docu-mented in the literature that the initial (that is, 0 to 15C)freezing condition causes

28、the most significant effects3inhydraulic conductivity. Freezing rate and ultimate temperatureshould mimic the field conditions. It has been shown thatsuperfreezing (that is, freezing the specimen at very coldtemperatures and very short time periods) produces erroneousresults.4.6 The thawed specimen

29、temperature and thaw rate shallmimic field conditions. Thawing specimens in an oven (that is,overheating) will produce erroneous results.4.7 Literature relating to this subject indicates that theeffects of freeze-thaw usually occur by Cycle 10, thus it isrecommended that at least 10 freeze-thaw cycl

30、es shall beperformed to ensure that the full effects of freeze-thaw aremeasured. If the hydraulic conductivity values are still increas-ing after 10 freeze-thaw cycles, the test method shall becontinued (that is, more freeze-thaw cycles shall be per-formed).5. Apparatus5.1 Freezing Cabinet, capable

31、of maintaining at least 1561C.5.2 The apparatus listed in Test Method D 5084 (see 5.1through section 5.18).6. Reagents6.1 Deaired WaterTo aid in removing as much air fromthe specimen as possible during the hydraulic conductivityportion of the test, deaired water shall be used.6.2 OptionalIf the spec

32、imen is frozen/thawed in theflexiwall permeameter, a mixture of propylene glycol and tapwater can be placed in the flexi-wall permeameter cell. Thecompatibility of the mixture and membrane used shall bedetermined. Membranes may degrade and cause cell leakage.This mixture should have a freezing point

33、 lower than theambient temperature of the freezing cabinet. The specimen willfreeze, but the cell fluid will not. This allows the total stress onthe specimen to remain unchanged during the freeze-thawprocedures.7. Test Specimens7.1 SizeThe size of the specimen depends on the type andsize of permeame

34、ter being used for the hydraulic conductivitytesting. The specimen shall have a minimum diameter of 71.1mm (2.80 in.) or greater and a minimum height of 71.1 mm.The height and diameter of the specimen shall be measured tothe nearest 0.3 mm (0.01 in.) or better. The length and diametershall not vary

35、by more than 65 %. For specimen diameters of71.1 mm, clods less than 12.7 mm (0.5 in.) shall not be6Annual Book of ASTM Standards, Vol 14.02.7McManus, A. C., Werthman, P. H., and McManus, K. R., “Evaluation of theEffects of Frost Action on the Permeability of a Compacted Soil,” presented at theNew Y

36、ork State Association of Solid Waste Management Fall Program, LakeLuzerne, NY, October 1989.D6035022reduced. For specimen diameters of 101.6 mm (4.00 in.), clodsizes less than 17.0 mm (0.67 in.) shall not be reduced. Thesurface of the test specimen may be uneven, but indentationsmust not be so deep

37、that the length or diameter of the specimenvaries by more than 65 %. The diameter and height of thespecimen shall each be at least 6 times greater than the largestparticle size within the specimen. After completion of the testmethod, if oversized particles are found, it should be noted inthe report.

38、7.2 Undisturbed or laboratory-compacted specimens can beused with this methodology. Test Method D 5084 shall befollowed to prepare undisturbed or laboratory-compactedspecimens.7.3 Number of Test SpecimensThis test method providesTest Method A and Test Method B for performing the test.7.3.1 Test Meth

39、od AA specimen shall be prepared foreach hydraulic conductivity determination performed. Forexample, if the hydraulic conductivity is performed initially,after 5 cycles and finally after 10 freeze-thaw cycles, a total of3 specimens would be required. One specimen would be usedfor the initial hydraul

40、ic conductivity, the second specimenhydraulic conductivity would be determined after subjectingthe specimen to 5 freeze-thaw cycles and the third specimenhydraulic conductivity would be determined after subjectingthe specimen to 10 freeze-thaw cycles. This test methodrequires similar specimen prepar

41、ation methods to ensure thatrepresentative samples are used (see Note 3).7.3.2 Test Method BOne specimen can be used for theentire test method. This is not recommended for specimenswith initial moisture contents significantly lower than 100 %saturation of the soil (Note 3).NOTE 3Using more than one

42、specimen offers the advantage ofcomparison of hydraulic conductivities at an unchanging moisture con-tent. When using one specimen for the entire test, the initial hydraulicconductivity test saturates the specimen producing a specimen for thefreeze-thaw cycles that has a moisture content increased f

43、rom the originalcompacted moisture content. This test method allows either procedure;however cautions the user about the moisture content. The results shouldnot be significantly different if the initial moisture content is almost atsaturation, which is the case if soils are compacted well above opti

44、mummoisture content. Using more than one specimen for the test method,specifically undisturbed specimens, has the disadvantage of potentialnonrepresentative specimens and test results that are not comparable.7.3.3 Undisturbed SpecimensUndisturbed test specimensshall be prepared from a representative

45、 portion of undisturbedspecimens secured in accordance with Practice D 1587 orPractice D 2113, and preserved and transported in accordancewith requirements for Group C materials in Practice D 4220(refer to Test Method D 5084 for further discussion).7.3.4 Laboratory Compacted Specimens Refer to TestM

46、ethod D 5084. Specimens shall be compacted in a mold orpiece of PVC pipe or any other suitable apparatus so that thesamples are confined during the freeze-thaw cycles. The user ofthe test method can perform 1-d freeze-thaw by placinginsulation around the pipe and using a control sample with athermoc

47、ouple (see Note 4) or can perform 3-d freezing byplacing the pipe in the freezer without insulation.7.4 Other preparation test methods can be followed ifspecified and if identified in the report.7.5 Determine the water content (Test Method D 2216),height, diameter, and mass of each test specimen and

48、 calculatethe dry unit weight. The initial degree of saturation can beestimated.8. Procedure8.1 Determine the initial hydraulic conductivity of thespecimen following Test Method D 5084.8.2 Place the specimen in the freezing cabinet for approxi-mately 24 h (Note 4). The water content of the specimen

49、shouldnot be allowed to change during the freeze-thaw cycles. Thiscan be accomplished by placing each specimen in a plastic bag,or wrapping the specimens in saran wrap.8.3 After 24 h, remove the specimen from the freezingcabinet and place it in an environment with an ambienttemperature between 16C (60F) and 27C (80F) for 24 h(Note 4).NOTE 4The time of freezing or thawing the specimen can be reducedif a direct measurement of the temperature of the specimen can bemonitored using a thermocouple in a control specimen.8.4 Steps 8.2 and 8.3 combined shall constit