【astm標(biāo)準(zhǔn)】c 1012 - c 1012m - 15

1、Designation: C1012/C1012M ? 15Standard Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution1This standard is issued under the fixed designation C1012/C1012M; the number immediately foll

2、owing the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicate

3、s an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of length change of mortar bars immersed in a sulfate solution. Mortar bars made using mortar described i

4、n Test Method C109/ C109M are cured until they attain a compressive strength of 20.0 6 1.0 MPa [3000 6 150 psi], as measured using cubes made of the same mortar, before the bars are immersed.1.2 The values stated in eith

5、er SI units or inch-pound units are to be regarded separately as standard. Within the text, the inch-pound units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each syste

6、m shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associat

7、ed with its use. It is the responsibility 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 Documen

8、ts2.1 ASTM Standards:2C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens)C114 Test Methods for Chemical Analysis of Hydraulic CementC150 Specification for P

9、ortland Cement C157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and ConcreteC215 Test Method for Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete SpecimensC

10、305 Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic ConsistencyC348 Test Method for Flexural Strength of Hydraulic- Cement MortarsC349 Test Method for Compressive Strength of Hydraulic- C

11、ement Mortars (Using Portions of Prisms Broken in Flexure)C452 Test Method for Potential Expansion of Portland- Cement Mortars Exposed to SulfateC490 Practice for Use of Apparatus for the Determination of Length Change o

12、f Hardened Cement Paste, Mortar, and ConcreteC511 Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and ConcretesC595 Specification for Blended

13、Hydraulic Cements C597 Test Method for Pulse Velocity Through Concrete C618 Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in ConcreteC778 Specification for Sand C917 Test Method for Evaluati

14、on of Cement Strength Uni- formity From a Single SourceC989 Specification for Slag Cement for Use in Concrete and MortarsC1157 Performance Specification for Hydraulic Cement D1193 Specification for Reagent Water E18 Test

15、 Methods for Rockwell Hardness of Metallic Ma- terialsE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test M

16、ethod2.2 American Concrete Institute Reports: ACI C201-2R-01 Guide to Durable Concrete33. Significance and Use3.1 This test method provides a means of assessing the sulfate resistance of mortars made using portland cemen

17、t, blends of portland cement with pozzolans or slags, and blended1 This test method is under the jurisdiction of ASTM Committee C01 on Cement and is the direct responsibility of Subcommittee C01.29 on Sulfate Resistance.

18、 Current edition approved Oct. 1, 2015. Published October 2015. Originally approved in 1984. Last previous edition approved in 2012 as C1012/C1012M–13. DOI: 10.1520/C1012_C1012M-15. 2 For referenced ASTM standards, visit

19、 the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.3 Available f

20、rom American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http://www.concrete.org.*A Summary of Changes section appears at the end of this standardCopyright © ASTM International, 100 Bar

21、r Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States18.2.1 Prior to molding the test specimen, prepare the initial curing container by placing risers on the bottom of the container to elevate mold

22、s above the intended water level. Fill the container with preheated water at 35 6 3°C (95 6 5°F), making sure that the water does not exceed the top of the risers.9. Procedure9.1 Molding and Initial Curing of S

23、pecimens—Mold the test bars in accordance with Test Method C157/C157M. Mold the cubes in accordance with Test Method C109/C109M. A set of specimens to test one cementitious product consists of 6 bars and up to 21 cubes (

24、Note 2). Immediately after molding cover the molds with a rigid steel, glass, or plastic plate, and place the mold in the curing container on top of the risers. Cover the container with a lid and seal the lid so as to pr

25、event evaporation and place the container into an oven at 35 6 3°C (95 6 5°F) for 231?2 h 6 30 min. At 231?2 h 6 30 min, remove molds from container and demold the specimens.NOTE 2—The set of cubes consists of

26、21 cubes to be tested as described herein when significant information on the strength development rate is not available. When information is available (as for example, from the use of the procedures of Test Method C917)

27、 that would justify making fewer cubes, only those needed to confirm the time the mortar achieves 20.0 6 1.0 MPa [3000 6 150 psi] are needed.9.2 Subsequent Curing and Preparation for Test—After demolding, store all bars

28、and cubes, except the two to be tested, in a curing tank of saturated limewater at 23.0 6 2.0°C [73.5 6 3.5°F]. Test two cubes in compression in accordance with Test Method C109/C109M after demolding when the s

29、peci- mens have cooled to ambient temperature under moist cloths. If the mean strength of the two cubes is 20 MPa [2850 psi] or more, observe and record comparator readings in accordance with Specification C490 and as pr

30、escribed in the section on Measurements of Length Change and place all the bars in the sulfate solution. If 20 MPa [2850 psi] is not achieved, store the demolded cubes and mortar bars in the curing tank and test addition

31、al cubes (see Note 3). Predict from the first two cubes when a compressive strength of at least 20 MPa [2850 psi] will be reached. Verify the prediction, and at that time observe and record comparator readings and place

32、all the bars in the sulfate solution (Note 3). This measurement is designated as the initial length. The storage temperature and test temperature shall be 23.0 6 2.0°C [73.5 6 3.5°F].NOTE 3—If the value for str

33、ength at 24 h is less than 20.0 MPa [2850 psi] and additional testing on the same day is not possible, or, is unlikely to yield a value over 20.0 MPa [2850 psi] and the strength is over 21 MPa [3150 psi] when tested earl

34、y the next day, it is not necessary to remake the batch. If the two cubes do not meet the required strength, continue curing the cubes and bars as referenced in 9.2. in a curing tank of saturated limewater at 23.0 6 2.0&

35、#176;C [73.5 6 3.5°F]9.3 Storage of Test Bars during Exposure to Test Solution— Cover the container of the bars and test solution, and seal it to prevent evaporation from the inside, or dilution with water from the

36、outside. (See Note 4.) The storage temperature and test temperature shall be 23.0 6 2.0°C [73.5 6 3.5°F]. (See Note 5.)NOTE 4—Gaffers tape or duct tape has been found to be suitable for sealing the container. N

37、OTE 5—This is the same temperature and temperature range as thatspecified for moist rooms in Specification C511.9.4 Measurements of Length Change—At 1, 2, 3, 4, 8, 13, and 15 weeks after the bars are placed in the sulfat

38、e solution, test them for length change using the length comparator in accordance with Specification C490. Review the data at 15 weeks. Make the subsequent measurements at 4, 6, 9, and 12 months. If at any time the rate

39、of change between readings is great, insert other readings as needed to ensure the intervals are short enough to permit observing and reporting the behavior of the bars. If compliance with ACI C201-2R-01 Class 3 exposure

40、 is required, measure the bars at 4, 6, 9, 12, 15, and 18 months (Note 6).NOTE 6—ACI C201-2R-01 requires an 18-month limit for Class 3 exposure.9.4.1 Details of Measurement of Bars for Length Change:9.4.1.1 Clean the hol

41、e in the base of the comparator into which the gauge stud on the lower end of the bar fits (this hole tends to collect water and sand and should be cleaned after every reading). Read and record the comparator indication

42、of the length of the reference bar. Take one bar out of immersion, blot the pins, put the bar in the comparator, read, and record the indication. Return the bar to immersion and clean the hole in the base of the comparat

43、or. Take out the second bar and treat it in a like manner. Return the second bar to immersion, record the reading, and clean the hole in the base of the comparator. Continue the procedure until all bars have been read, r

44、eturned to immersion, and the readings recorded, cleaning the hole in the bottom of the comparator each time. After reading the last bar, clean the hole in the comparator base and read and record the reference-bar indica

45、tion.9.4.1.2 When the required strength of the mortar is achieved in accordance with 9.2, store the bars in fresh sulfate solution. At subsequent readings for length change, proceed as described in 9.4.1.1; cleaning the

46、socket in the base of the comparator before reading the reference bar initially and after reading each mortar bar. Record reference bar and mortar bar readings. Read and record the reference bar again after measurement o

47、f the last bar. Blot only around the pins (Note 7). Return each bar to the used sulfate solution after reading. Discard the used solution after reading of the bars at only standard intervals: 1, 2, 3, 4, 8, 13, and 15 we

48、eks and 4, 6, 9, 12, 15, and 18 months. Rinse the container once with water, pouring out water and debris. Replace the frame holding the bars in the container, fill the container with enough new sulfate solution to immer

49、se bars, and secure the lid on the container.NOTE 7—The purpose of the minimal blotting of the pins and no blotting of the bars is to avoid drying and shrinkage of the bars. It has been observed that if the pins are blot

50、ted, and the bar placed in the comparator and the dial read, and the bar is then wiped gently with a dry cloth, the bar will shrink measurably. Therefore, drying should be minimized.9.4.2 Examination of Specimens After M

51、easuring Length Change—When the bars seem to have behaved in an unusual way or when the test is part of a research study, test the specimens for warping by placing them on a plane surface so that the ends are curved down