ASTM C666 C666M-2003(2008) Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing《混凝土抗急速冻结溶解性能测试的标准试验方法》.pdf

1、Designation: C 666/C 666M 03 (Reapproved 2008)Standard Test Method forResistance of Concrete to Rapid Freezing and Thawing1This standard is issued under the fixed designation C 666/C 666M; the number immediately following the designation indicates the yearof original adoption or, in the case of revi

2、sion, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method co

3、vers the determination of the resis-tance of concrete specimens to rapidly repeated cycles offreezing and thawing in the laboratory by two differentprocedures: Procedure A, Rapid Freezing and Thawing inWater, and Procedure B, Rapid Freezing in Air and Thawing inWater. Both procedures are intended fo

4、r use in determining theeffects of variations in the properties of concrete on theresistance of the concrete to the freezing-and-thawing cyclesspecified in the particular procedure. Neither procedure isintended to provide a quantitative measure of the length ofservice that may be expected from a spe

5、cific type of concrete.1.2 The values stated in either inch-pound units or SI unitsshall be regarded separately as standard. The SI units areshown in brackets. The values stated may not be exactequivalents; therefore each system must be used independentlyof the other. Combining values from the two u

6、nits may resultin nonconformance.1.3 All material in this test method not specifically desig-nated as belonging to Procedure A or Procedure B applies toeither procedure.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility o

7、f 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:2C 157/C 157M Test Method for Length Change of Hard-ened Hydraulic-Cement Mortar and ConcreteC 192/C 192

8、M Practice for Making and Curing ConcreteTest Specimens in the LaboratoryC 215 Test Method for Fundamental Transverse, Longitu-dinal, and Torsional Resonant Frequencies of ConcreteSpecimensC 233 Test Method for Air-Entraining Admixtures for Con-creteC 295 Guide for Petrographic Examination of Aggreg

9、atesfor ConcreteC 341/C 341M Practice for Length Change of Cast, Drilled,or Sawed Specimens of Hydraulic-Cement Mortar andConcreteC 490 Practice for Use of Apparatus for the Determinationof Length Change of Hardened Cement Paste, Mortar, andConcreteC 494/C 494M Specification for Chemical Admixtures

10、forConcreteC 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC 823 Practice for Examination and Sampling of HardenedConcrete in Constructions3. Significance and Use3.1 As noted in the scope, the two procedures described inthis test method are intend

11、ed to determine the effects ofvariations in both properties and conditioning of concrete in theresistance to freezing and thawing cycles specified in theparticular procedure. Specific applications include specifieduse in Specification C 494/C 494M, Test Method C 233, andranking of coarse aggregates

12、as to their effect on concretefreeze-thaw durability, especially where soundness of theaggregate is questionable.3.2 It is assumed that the procedures will have no signifi-cantly damaging effects on frost-resistant concrete which maybe defined as (1) any concrete not critically saturated withwater (

13、that is, not sufficiently saturated to be damaged byfreezing) and (2) concrete made with frost-resistant aggregates1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.67 on Resistance to the Environm

14、ent.Current edition approved June 1, 2008. Published September 2008. Originallyapproved in 1971. Last previous edition approved in 2003 as C 666/C 666M 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM

15、Standards volume information, 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.and having an adequate air-void system that has achievedappropriate maturity and thus will

16、prevent critical saturation bywater under common conditions.3.3 If as a result of performance tests as described in thistest method concrete is found to be relatively unaffected, it canbe assumed that it was either not critically saturated, or wasmade with “sound” aggregates, a proper air-void syste

17、m, andallowed to mature properly.3.4 No relationship has been established between the resis-tance to cycles of freezing and thawing of specimens cut fromhardened concrete and specimens prepared in the laboratory.4. Apparatus4.1 Freezing-and-Thawing Apparatus:4.1.1 The freezing-and-thawing apparatus

18、shall consist of asuitable chamber or chambers in which the specimens may besubjected to the specified freezing-and-thawing cycle, togetherwith the necessary refrigerating and heating equipment andcontrols to produce continuously, and automatically, reproduc-ible cycles within the specified temperat

19、ure requirements. Inthe event that the equipment does not operate automatically,provision shall be made for either its continuous manualoperation on a 24-h a day basis or for the storage of allspecimens in a frozen condition when the equipment is not inoperation.4.1.2 The apparatus shall be so arran

20、ged that, except fornecessary supports, each specimen is: (1) for Procedure A,completely surrounded by not less than132 in. 1 mm normore than18 in. 3 mm of water at all times while it is beingsubjected to freezing-and-thawing cycles, or (2) for ProcedureB, completely surrounded by air during the fre

21、ezing phase ofthe cycle and by water during the thawing phase. Rigidcontainers, which have the potential to damage specimens, arenot permitted. Length change specimens in vertical containersshall be supported in a manner to avoid damage to the gagestuds.NOTE 1Experience has indicated that ice or wat

22、er pressure, duringfreezing tests, particularly in equipment that uses air rather than a liquidas the heat transfer medium, can cause excessive damage to rigid metalcontainers, and possibly to the specimens therein. Results of tests duringwhich bulging or other distortion of containers occurs should

23、 be inter-preted with caution.4.1.3 The temperature of the heat-exchanging medium shallbe uniform within 6 F 3 C throughout the specimen cabinetwhen measured at any given time, at any point on the surfaceof any specimen container for Procedure A or on the surface ofany specimen for Procedure B, exce

24、pt during the transitionbetween freezing and thawing and vice versa.4.1.3.1 Support each specimen at the bottom of its containerin such a way that the temperature of the heat-exchangingmedium will not be transmitted directly through the bottom ofthe container to the full area of the bottom of the sp

25、ecimen,thereby subjecting it to conditions substantially different fromthe remainder of the specimen.NOTE 2A flat spiral of18-in. 3-mm wire placed in the bottom of thecontainer has been found adequate for supporting specimens.4.1.4 For Procedure B, it is not contemplated that thespecimens will be ke

26、pt in containers. The supports on whichthe specimens rest shall be such that they are not in contactwith the full area of the supported side or end of the specimen,thereby subjecting this area to conditions substantially differentfrom those imposed on the remainder of the specimen.NOTE 3The use of r

27、elatively open gratings, metal rods, or the edgesof metal angles has been found adequate for supporting specimens,provided the heat-exchanging medium can circulate in the direction of thelong axis of the rods or angles.4.2 Temperature-Measuring Equipment, consisting of ther-mometers, resistance ther

28、mometers, or thermocouples, capableof measuring the temperature at various points within thespecimen chamber and at the centers of control specimens towithin 2 F 1 C.4.3 Dynamic Testing Apparatus, conforming to the require-ments of Test Method C 215.4.4 Optional Length Change Test Length Change Comp

29、ara-tor, conforming to the requirements of Specification C 490.When specimens longer than the nominal 1114 in. 285 mmlength provided for in Specification C 490 are used for freeze-thaw tests, use an appropriate length reference bar, whichotherwise meets the Specification C 490 requirements. Dialgage

30、 micrometers for use on these longer length changecomparators shall meet the gradation interval and accuracyrequirements for Specification C 490 for either the inch ormillimetre calibration requirements. Prior to the start of mea-surements on any specimens, fix the comparator at an appro-priate leng

31、th to accommodate all of the specimens to bemonitored for length change.4.5 Scales, with a capacity approximately 50 % greater thanthe mass of the specimens and accurate to at least 0.01 lb 0.5g within the range of 610 % of the specimen mass will besatisfactory.4.6 Tempering Tank, with suitable prov

32、isions for maintain-ing the temperature of the test specimens in water, such thatwhen removed from the tank and tested for fundamentaltransverse frequency and length change, the specimens will bemaintained within -2 F and +4 F (-1 C and +2 C) of thetarget thaw temperature for specimens in the actual

33、 freezing-and-thawing cycle and equipment being used. The use of thespecimen chamber in the freezing-and-thawing apparatus bystopping the apparatus at the end of the thawing cycle andholding the specimens in it shall be considered as meeting thisrequirement, provided the specimens are tested for fun

34、damen-tal transverse frequency within the above temperature range. Itis required that the same target specimen thaw temperature beused throughout the testing of an individual specimen since achange in specimen temperature at the time of length measure-ment can affect the length of the specimen signi

35、ficantly.5. Freezing-and-Thawing Cycle5.1 Base conformity with the requirements for the freezing-and-thawing cycle on temperature measurements of controlspecimens of similar concrete to the specimens under test inwhich suitable temperature-measuring devices have been im-bedded. Change the position o

36、f these control specimens fre-quently in such a way as to indicate the extremes of tempera-ture variation at different locations in the specimen cabinet.C 666/C 666M 03 (2008)25.2 The nominal freezing-and-thawing cycle for both pro-cedures of this test method shall consist of alternately loweringthe

37、 temperature of the specimens from 40 to 0 F 4 to -18 Cand raising it from 0 to 40 F -18 to 4 C in not less than 2nor more than 5 h. For Procedure A, not less than 25 % of thetime shall be used for thawing, and for Procedure B, not lessthan 20 % of the time shall be used for thawing (Note 4).At thee

38、nd of the cooling period the temperature at the centers of thespecimens shall be 0 6 3 F -18 6 2 C, and at the end of theheating period the temperature shall be 40 6 3F46 2 C,with no specimen at any time reaching a temperature lowerthan -3 F -19 C nor higher than 43 F 6 C. The timerequired for the t

39、emperature at the center of any singlespecimen to be reduced from 37 to 3 F 3 to -16 C shall benot less than one half of the length of the cooling period, andthe time required for the temperature at the center of any singlespecimen to be raised from 3 to 37 F -16 to 3 C shall be notless than one hal

40、f of the length of the heating period. Forspecimens to be compared with each other, the time required tochange the temperature at the centers of any specimens from 35to 10 F 2 to -12 C shall not differ by more than one sixth ofthe length of the cooling period from the time required for anyspecimen a

41、nd the time required to change the temperature atthe centers of any specimens from 10 to 35 F -12 to 2 Cshall not differ by more than one third of the length of theheating period from the time required for any specimen.NOTE 4In most cases, uniform temperature and time conditions canbe controlled mos

42、t conveniently by maintaining a capacity load ofspecimens in the equipment at all times. In the event that a capacity loadof test specimens is not available, dummy specimens can be used to fillempty spaces. This procedure also assists greatly in maintaining uniformfluid level conditions in the speci

43、men and solution tanks.The testing of concrete specimens composed of widely varying mate-rials or with widely varying thermal properties, in the same equipment atthe same time, may not permit adherence to the time-temperaturerequirements for all specimens. It is advisable that such specimens beteste

44、d at different times and that appropriate adjustments be made to theequipment.5.3 The difference between the temperature at the center ofa specimen and the temperature at its surface shall at no timeexceed 50 F 28 C.5.4 The period of transition between the freezing-and-thawing phases of the cycle sh

45、all not exceed 10 min, exceptwhen specimens are being tested in accordance with 8.3.6. Sampling6.1 Constituent materials for concrete specimens made inthe laboratory shall be sampled using applicable standardmethods.6.2 Samples cut from hardened concrete are to be obtainedin accordance with Practice

46、 C 823.7. Test Specimens7.1 The specimens for use in this test method shall beprisms or cylinders made and cured in accordance with theapplicable requirements of Practice C 192/C 192M and Speci-fication C 490.7.2 Specimens used shall not be less than 3 in. 75 mm normore than 5 in. 125 mm in width, d

47、epth, or diameter, and notless than 11 in. 275 mm nor more than 16 in. 405 mm inlength.7.3 Test specimens may also be cores or prisms cut fromhardened concrete. If so, the specimens should not be allowedto dry to a moisture condition below that of the structure fromwhich taken. This may be accomplis

48、hed by wrapping in plasticor by other suitable means. The specimens so obtained shall befurnished with gage studs in accordance with Test MethodC 341/C 341M.7.4 For this test the specimens shall be stored in saturatedlime water from the time of their removal from the molds untilthe time freezing-and

49、-thawing tests are started. All specimensto be compared with each other initially shall be of the samenominal dimensions.8. Procedure8.1 Molded beam specimens shall be cured for 14 days priorto testing unless otherwise specified. Beam specimens sawedfrom hardened concrete shall be moisture-conditioned byimmersing in saturated lime water at 73.4 6 3 F 23.0 6 2.0C for 48 h prior to testing unless otherwise specified.8.2 Immediately after the specified curing or conditioningperiod, bring the specimen