ASTM C666 C666M-2015 Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing《混凝土抗急速冻结和解冻的标准试验方法》.pdf

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1、Designation: C666/C666M 03 (Reapproved 2008)C666/C666M 15Standard Test Method forResistance of Concrete to Rapid Freezing and Thawing1This standard is issued under the fixed designation C666/C666M; the number immediately following the designation indicates the yearof original adoption or, in the cas

2、e of revision, 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 U.S. Department of Defense.1. Scope Scope*1.

3、1 This test method covers the determination of the resistance of concrete specimens to rapidly repeated cycles of freezing andthawing in the laboratory by two different procedures: ProcedureA, Rapid Freezing and Thawing in Water, and Procedure B, RapidFreezing inAir andThawing inWater. Both procedur

4、es are intended for use in determining the effects of variations in the propertiesof concrete on the resistance of the concrete to the freezing-and-thawing cycles specified in the particular procedure. Neitherprocedure is intended to provide a quantitative measure of the length of service that may b

5、e expected from a specific type ofconcrete.1.2 The values stated in either inch-pound units or SI units shall be regarded separately as standard. The SI units are shown inbrackets. The values stated may not be exact equivalents; therefore each system must be used independently of the other.Combining

6、 values from the two units may result in nonconformance.1.3 All material in this test method not specifically designated as belonging to Procedure A or Procedure B applies to eitherprocedure.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It

7、 is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Co

8、ncreteC192/C192M Practice for Making and Curing Concrete Test Specimens in the LaboratoryC215 Test Method for Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete SpecimensC233 Test Method for Air-Entraining Admixtures for ConcreteC295 Guide for Petrographic Examinati

9、on of Aggregates for ConcreteC341/C341M Practice for Preparation and Conditioning of Cast, Drilled, or Sawed Specimens of Hydraulic-Cement Mortar andConcrete Used for Length Change MeasurementsC490 Practice for Use of Apparatus for the Determination of Length Change of Hardened Cement Paste, Mortar,

10、 and ConcreteC494/C494M Specification for Chemical Admixtures for ConcreteC670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction MaterialsC823 Practice for Examination and Sampling of Hardened Concrete in Constructions2.2 ASTM STP:2ASTM STP 169C and D1, 2 Signifi

11、cance of Tests and Properties of Concrete and Concrete-Making Materials3. Significance and Use3.1 As noted in the scope, the two procedures described in this test method are intended to determine the effects of variationsin both properties and conditioning of concrete in the resistance to freezing a

12、nd thawing cycles specified in the particular1 This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregatesand is the direct responsibility of Subcommittee C09.67 onResistance to the Environment.Current edition approved June 1, 2008Feb. 1, 2015. Published Sept

13、ember 2008March 2015. Originally approved in 1971. Last previous edition approved in 20032008 asC666/C666M 03.C666/C666M 03 (2008). DOI: 10.1520/C0666_C0666M-03R08.10.1520/C0666_C0666M-15.2 For referenced ASTM standards, standards and Special Technical Publications (STPs), visit the ASTM website, ww

14、w.astm.org, or contact ASTM Customer Service atserviceastm.org. For Annual Book of ASTM Standards volume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of w

15、hat changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered t

16、he official document.*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 States1procedure. Specific applications include specified use in Specification C494/C494M, Test Method C233

17、, and ranking of coarseaggregates as to their effect on concrete freeze-thaw durability, especially where soundness of the aggregate is questionable.3.2 It is assumed that the procedures will have no significantly damaging effects on frost-resistant concrete which may bedefined as (1) any concrete n

18、ot critically saturated with water (that is, not sufficiently saturated to be damaged by freezing) and(2) concrete made with frost-resistant aggregates and having an adequate air-void system that has achieved appropriate maturityand thus will prevent critical saturation by water under common conditi

19、ons.3.3 If as a result of performance tests as described in this test method concrete is found to be relatively unaffected, it can beassumed that it was either not critically saturated, or was made with “sound” aggregates, a proper air-void system, and allowedto mature properly.3.4 No relationship h

20、as been established between the resistance to cycles of freezing and thawing of specimens cut fromhardened concrete and specimens prepared in the laboratory.3.5 There is no specific guidance on choosing between Procedure A and Procedure B for a given application, except whencontained in a specificat

21、ion. Specifications C233 and C494/C494M both stipulate Procedure A. In many instances the choice isbased on the users determination of suitability to a specific application. Procedure A is generally considered to be the moreaggressive of the two and to better reveal defective materials, although som

22、e consider the constant saturation of the test specimensto be unrealistic. Some users prefer Procedure B as being more representative of the saturation patterns in some field applications.The history of this standard and a more complete discussion of significance and use can be found in ASTM STP 169

23、C and D1,2.4. Apparatus4.1 Freezing-and-Thawing Apparatus:4.1.1 The freezing-and-thawing apparatus shall consist of a suitable chamber or chambers in which the specimens may besubjected to the specified freezing-and-thawing cycle, together with the necessary refrigerating and heating equipment and c

24、ontrolsto produce continuously, and automatically, reproducible cycles within the specified temperature requirements. In the event thatthe equipment does not operate automatically, provision shall be made for either its continuous manual operation on a 24-h a daybasis or for the storage of all speci

25、mens in a frozen condition when the equipment is not in operation.4.1.2 The apparatus shall be so arranged that, except for necessary supports, each specimen is: (1) for Procedure A, completelysurrounded by not less than 132 in. 1 mm nor more than 18 in. 3 mm of water at all times while it is being

26、subjected tofreezing-and-thawing cycles, or (2) for Procedure B, completely surrounded by air during the freezing phase of the cycle and bywater during the thawing phase. Rigid containers, which have the potential to damage specimens, are not permitted. Length changespecimens in vertical containers

27、shall be supported in a manner to avoid damage to the gage studs.NOTE 1Experience has indicated that ice or water pressure, during freezing tests, particularly in equipment that uses air rather than a liquid as theheat transfer medium, can cause excessive damage to rigid metal containers, and possib

28、ly to the specimens therein. Results of tests during which bulgingor other distortion of containers occurs should be interpreted with caution.4.1.3 The temperature of the heat-exchanging medium shall be uniform within 6 F 3 C throughout the specimen cabinetwhen measured at any given time, at any poi

29、nt on the surface of any specimen container for Procedure A or on the surface of anyspecimen for Procedure B, except during the transition between freezing and thawing and vice versa.4.1.3.1 Support each specimen at the bottom of its container in such a way that the temperature of the heat-exchangin

30、g mediumwill not be transmitted directly through the bottom of the container to the full area of the bottom of the specimen, therebysubjecting it to conditions substantially different from the remainder of the specimen.NOTE 2A flat spiral of 18-in. 3-mm wire placed in the bottom of the container has

31、 been found adequate for supporting specimens.4.1.4 For Procedure B, it is not contemplated that the specimens will be kept in containers. The supports on which the specimensrest shall be such that they are not in contact with the full area of the supported side or end of the specimen, thereby subje

32、ctingthis area to conditions substantially different from those imposed on the remainder of the specimen.NOTE 3The use of relatively open gratings, metal rods, or the edges of metal angles has been found adequate for supporting specimens, providedthe heat-exchanging medium can circulate in the direc

33、tion of the long axis of the rods or angles.4.2 Temperature-Measuring Equipment, consisting of thermometers, resistance thermometers, or thermocouples, capable ofmeasuring the temperature at various points within the specimen chamber and at the centers of control specimens to within 2 F1 C.4.3 Dynam

34、ic Testing Apparatus, conforming to the requirements of Test Method C215.4.4 Optional Length Change Test Length Change Comparator, conforming to the requirements of Specification C490. Whenspecimens longer than the nominal 1114 in. 285 mm length provided for in Specification C490 are used for freeze

35、-thaw tests, usean appropriate length reference bar, which otherwise meets the Specification C490 requirements. Dial gage micrometers for useon these longer length change comparators shall meet the gradation interval and accuracy requirements for Specification C490 forC666/C666M 152either the inch o

36、r millimetre calibration requirements. Prior to the start of measurements on any specimens, fix the comparator atan appropriate length to accommodate all of the specimens to be monitored for length change.4.5 Scales, with a capacity approximately 50 % greater than the mass of the specimens and accur

37、ate to at least 0.01 lb 0.5 gwithin the range of 610 % of the specimen mass will be satisfactory.4.6 Tempering Tank, with suitable provisions for maintaining the temperature of the test specimens in water, such that whenremoved from the tank and tested for fundamental transverse frequency and length

38、 change, the specimens will be maintainedwithin -2 F and +4 F (-1 C and +2 C) of the target thaw temperature for specimens in the actual freezing-and-thawing cycleand equipment being used. The use of the specimen chamber in the freezing-and-thawing apparatus by stopping the apparatus atthe end of th

39、e thawing cycle and holding the specimens in it shall be considered as meeting this requirement, provided thespecimens are tested for fundamental transverse frequency within the above temperature range. It is required that the same targetspecimen thaw temperature be used throughout the testing of an

40、 individual specimen since a change in specimen temperature atthe time of length measurement can affect the length of the specimen significantly.5. Freezing-and-Thawing Cycle5.1 Base conformity with the requirements for the freezing-and-thawing cycle on temperature measurements of controlspecimens o

41、f similar concrete to the specimens under test in which suitable temperature-measuring devices have been imbedded.Change the position of these control specimens frequently in such a way as to indicate the extremes of temperature variation atdifferent locations in the specimen cabinet.5.2 The nominal

42、 freezing-and-thawing cycle for both procedures of this test method shall consist of alternately lowering thetemperature of the specimens from 40 to 0 F 4 to -18 C and raising it from 0 to 40 F -18 to 4 C in not less than 2 nor morethan 5 h. For Procedure A, not less than 25 % of the time shall be u

43、sed for thawing, and for Procedure B, not less than 20 % ofthe time shall be used for thawing (Note 4). At the end of the cooling period the temperature at the centers of the specimens shallbe 0 6 3 F -18 6 2 C, and at the end of the heating period the temperature shall be 40 6 3 F 4 6 2 C, with no

44、specimenat any time reaching a temperature lower than -3 F -19 C nor higher than 43 F 6 C. The time required for the temperatureat the center of any single specimen to be reduced from 37 to 3 F 3 to -16 C shall be not less than one half of the length ofthe cooling period, and the time required for t

45、he temperature at the center of any single specimen to be raised from 3 to 37 F -16to 3 C shall be not less than one half of the length of the heating period. For specimens to be compared with each other, the timerequired to change the temperature at the centers of any specimens from 35 to 10 F 2 to

46、 -12 C shall not differ by more thanone sixth of the length of the cooling period from the time required for any specimen and the time required to change thetemperature at the centers of any specimens from 10 to 35 F -12 to 2 C shall not differ by more than one third of the lengthof the heating peri

47、od from the time required for any specimen.NOTE 4In most cases, uniform temperature and time conditions can be controlled most conveniently by maintaining a capacity load of specimensin the equipment at all times. In the event that a capacity load of test specimens is not available, dummy specimens

48、can be used to fill empty spaces. Thisprocedure also assists greatly in maintaining uniform fluid level conditions in the specimen and solution tanks.The testing of concrete specimens composed of widely varying materials or with widely varying thermal properties, in the same equipment at the sametim

49、e, may not permit adherence to the time-temperature requirements for all specimens. It is advisable that such specimens be tested at different timesand that appropriate adjustments be made to the equipment.5.3 The difference between the temperature at the center of a specimen and the temperature at its surface shall at no time exceed50 F 28 C.5.4 The period of transition between the freezing-and-thawing phases of the cycle shall not exceed 10 min, except whenspecimens are being tested in accordance wi