1、Designation:C1012/C1012M10 Designation: C1012/C1012M 12Standard Test Method forLength Change of Hydraulic-Cement Mortars Exposed to aSulfate Solution1This standard is issued under the fixed designation C1012/C1012M; the number immediately following the designation indicates theyear of original adopt
2、ion or, in the case of 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. Scope*1.1 This test method covers the determination of length change of mortar bar
3、s immersed in a sulfate solution. Mortar bars madeusing mortar described in Test Method C109/C109M are cured until they attain a compressive strength of 20.0 6 1.0 MPa 30006 150 psi, as measured using cubes made of the same mortar, before the bars are immersed.1.2 The values stated in either SI unit
4、s or inch-pound units are to be regarded separately as standard. Within the text, theinch-pound units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shallbe used independently of the other. Combining values from the two systems may result
5、 in non-conformance with the standard.1.3 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 applicability of regulatorylimi
6、tations prior to use.2. Referenced Documents2.1 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 Portland CementC157/C157M Test Method for
7、 Length Change of Hardened Hydraulic-Cement Mortar and ConcreteC215 Test Method for Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete SpecimensC305 Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic ConsistencyC348 Test Method for Flex
8、ural Strength of Hydraulic-Cement MortarsC349 Test Method for Compressive Strength of Hydraulic-Cement 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
9、 Length Change of Hardened Cement Paste, Mortar, and ConcreteC511 Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing ofHydraulic Cements and ConcretesC595 Specification for Blended Hydraulic CementsC597 Test Method for Pulse Velocity Through Conc
10、reteC618 Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in ConcreteC684 Test Method for Making, Accelerated Curing, and Testing Concrete Compression Test SpecimensC778 Specification for SandC917 Test Method for Evaluation of Cement Strength Uniformity From a Single Sourc
11、eC989 Specification for Slag Cement for Use in Concrete and MortarsD1193 Specification for Reagent WaterE18 Test Methods for Rockwell Hardness of Metallic Materials2.2 American Concrete Institute Reports:ACI C201-2R-01 Guide to Durable Concrete31This test method is under the jurisdiction of ASTM Com
12、mittee C01 on Cement and is the direct responsibility of Subcommittee C01.29 on Sulfate Resistance.Current edition approved Dec. 15, 2010. Published January 2011. Originally approved in 1984. Last previous edition approved in 2009 as C1012/C1012M09. DOI:10.1520/C1012_C1012M-10.Current edition approv
13、ed April 1, 2012. Published May 2012. Originally approved in 1984. Last previous edition approved in 2010 as C1012/C1012M10. DOI:10.1520/C1012_C1012M-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM
14、Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:/www.concrete.org.1This document is not an ASTM standard and is intended only to provide the user of a
15、n 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 consult prior editions as appropriate. In all cases only the current versionof the standard as publi
16、shed by ASTM is to be considered the official document.*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.3. Significance and Use3.1 This test method provides a means of a
17、ssessing the sulfate resistance of mortars made using portland cement, blends ofportland cement with pozzolans or slags, and blended hydraulic cements. Method C452 is suitable for evaluating portland cementsbut not blended cements or blends of portland cement with pozzolans or slags.3.2 The standard
18、 exposure solution used in this test method, unless otherwise directed, contains 352 moles of Na2SO4per m3(50 g/L). Other sulfate concentrations or other sulfates such as MgSO4may be used to simulate the environmental exposure ofinterest. Further discussion of these and other technical issues is giv
19、en in the Appendix.4. Apparatus4.1 Mixer, conforming to the requirements of Practice C305.4.2 Cube Molds, conforming to the requirements of Test Method C109/C109M.4.3 Bar Molds, conforming to the requirements of Specification C490.4.4 Comparator, conforming to the requirements of Specification C490.
20、4.5 ContainersThe containers in which the bars are immersed shall be corrosion resistent such as plastic, glass, or ceramic.Support the bars so that no end or side of a bar rests against the container. Seal the container with a lid so that the sulfate solutioncannot evaporate.4.6 Curing Tank, confor
21、ming to the requirements of Test Method C684.5. Reagents and Materials5.1 Purity of ReagentsUSP or technical grade chemicals may be used, provided it is established that any reagent used is ofsufficiently high purity to permit its use without lessening the accuracy of the determination. When tests a
22、re made that are expectedto produce results that are close to an acceptance-rejection value, it is recommended that reagent grade chemicals be used. Suchchemicals shall conform to the specifications of the Committee on Analytical Reagents for the American Chemical Society wheresuch specifications ar
23、e available.45.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water conforming toType IV of Specification D1193.5.3 Sodium Sulfate (Na2SO4)Check the water content by loss on ignition each time the solution is prepared. Any anhydrousor hydrated so
24、dium sulfate may be used if the water content of the salt is checked by loss on ignition and proper corrections madeto account for the specified sulfate concentration.5.4 Sulfate SolutionEach litre of solution shall contain 50.0 g of Na2SO4dissolved in 900 mL of water, and shall be dilutedwith addit
25、ional distilled or deionized water to obtain 1.0 L of solution. Mix the solution on the day before use, cover, and storeat 23.0 6 2.0 C 73.5 6 3.5 F. Determine the pH of the solution before use; reject the solution if the pH range is outside 6.0to 8.0. Maintain the volume proportion of sulfate solut
26、ion to mortar bars in a storage container at 4.0 6 0.5 volumes of solutionto 1 volume of mortar bars. For mortar bars 1 by 1 by 1114 in. (volume of 184 mL 11.25 in.3), this is 645 to 830 mL of solutionper mortar bar in the storage container. For mortar bars 25 by 25 by 285 mm (volume 178 mL), this i
27、s 625 to 800 mL of solutionper mortar bar in the storage container.5.5 Materials:5.5.1 Graded Standard Sand, as specified in Specification C778.5.5.2 Stainless Steel Gauge Studs, as specified in Specification C490.6. Hazards6.1 WarningFresh hydraulic cementitious mixtures are caustic and may cause c
28、hemical burns to skin and tissue uponprolonged exposure.57. Preparing Mortars7.1 Make mortars as described in Test Method C109/C109M, that is, 1 part cement to 2.75 parts of sand by mass. Use awater-cement ratio by mass of 0.485 for all non-air-entraining portland cements and 0.460 for all air-entra
29、ining portland cements.Use a water-cement ratio by mass of 0.485 for non-air-entraining portland-pozzolan (IP) and portland-blast furnace slag (IS)cements. For blends of portland cement with a pozzolan or slag, use a water-cement ratio that develops a flow within 65 of thatof the portland-cement mor
30、tar at a water-cement ratio of 0.485.8. Specimen Molds8.1 Prepare the specimen molds in accordance with the requirements of Specification C490 except the interior surfaces of themold shall be covered with a release agent. A release agent will be acceptable if it serves as a parting agent without aff
31、ecting the4Reagent Chemicals, American Chemical Society Specifications , American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United Stat
32、es Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.5See Manual of Cement Testing, Section on Safety, Annual Book of ASTM Standards, Vol 04.01.C1012/C1012M 122setting of the cement and without leaving any residue that will inhibit the penetration of water
33、 into the specimen.NOTE 1TFE-fluorocarbon tape complies with the requirements for a mold release agent.9. Procedure9.1 Molding and Initial Curing of SpecimensMold the test bars in accordance with Test Method C157/C157M. Mold thecubes in accordance with Test Method C109/C109M. A set of specimens to t
34、est one cement consists of 6 bars and up to 21 cubes(Note 2). Immediately after molding, cover the molds with a rigid steel, glass, or plastic plate, seal the plate to the mold so as tobe watertight, and place the mold in the curing tank in water at 35 6 3C956 5 F for 2312 h 6 30 min, as in Test Met
35、hodC684, Procedure A (Warm-Water Method). Place the sealed molds in the curing tank with the bottom of the bars as cast down,that is, in the same relative position in which the bars were cast. At 2312 h 6 30 min, remove molds from tank and demold thespecimens.NOTE 2The set of cubes consists of 21 cu
36、bes to be tested as described herein when significant information on the strength development rate is notavailable. When information is available (as for example, from the use of the procedures of Test Method C917) that would justify making fewer cubes,only those needed to confirm the time the morta
37、r achieves 20.0 6 1.0 MPa 3000 6 150 psi are needed.9.2 Subsequent Curing and Preparation for TestAfter demolding, store all bars and cubes, except the two to be broken, ina curing tank of saturated limewater at 23.0 6 2.0 C 73.5 6 3.5 F. Break two cubes in compression in accordance with TestMethod
38、C109/C109M after demolding when the specimens have cooled to ambient temperature under moist cloths. If the meanstrength of the two cubes is 20 MPa 2850 psi or more, observe and record comparator readings in accordance with SpecificationC490 and as prescribed in the section on Measurements of Length
39、 Change and place all the bars in the sulfate solution. If 20 MPa2850 psi is not achieved, store the demolded cubes and mortar bars in the curing tank and test additional cubes. Predict from thefirst two cubes when a compressive strength of at least 20 MPa 2850 psi will be reached. Verify the predic
40、tion, and at that timeobserve and record comparator readings and place all the bars in the sulfate solution (Note 3). This measurement is designated asthe initial length. The storage temperature and test temperature shall be 23.0 6 2.0 C 73.5 6 3.5F.NOTE 3If the value for strength at 24 h is less th
41、an 20.0 MPa 2850 psi and additional testing on the same day is not possible, or, is unlikely to yielda value over 20.0 MPa 2850 psi and the strength is over 21 MPa 3150 psi when tested early the next day, it is not necessary to remake the batch.9.3 Storage of Test Bars during Exposure to Test Soluti
42、onCover the container of the bars and test solution, and seal it toprevent evaporation from the inside, or dilution with water from the outside. (See Note 4.) The storage temperature and testtemperature shall be 23.0 6 2.0 C 73.5 6 3.5 F. (See Note 5.)NOTE 4Gaffers tape or duct tape has been found t
43、o be suitable for sealing the container.NOTE 5This is the same temperature and temperature range as that specified for moist rooms in Specification C511.9.4 Measurements of Length ChangeAt 1, 2, 3, 4, 8, 13, and 15 weeks after the bars are placed in the sulfate solution, testthem for length change u
44、sing the length comparator in accordance with Specification C490. Review the data at 15 weeks. Makethe subsequent measurements at 4, 6, 9, and 12 months. If at any time the rate of change between readings is great, insert otherreadings as needed to ensure the intervals are short enough to permit obs
45、erving and reporting the behavior of the bars. Ifcompliance with ACI C201-2R-01 Class 3 exposure is required, measure the bars at 4, 6, 9, 12, 15, and 18 months (Note 6).NOTE 6ACI 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.
46、1 Clean the hole in the base of the comparator into which the gauge stud on the lower end of the bar fits (this hole tendsto collect water and sand and should be cleaned after every reading). Read and record the comparator indication of the length ofthe reference bar. Take one bar out of immersion,
47、blot the pins, put the bar in the comparator, read, and record the indication. Returnthe bar to immersion and clean the hole in the base of the comparator. Take out the second bar and treat it in a like manner. Returnthe second bar to immersion, record the reading, and clean the hole in the base of
48、the comparator. Continue the procedure untilall bars have been read, returned to immersion, and the readings recorded, cleaning the hole in the bottom of the comparator eachtime. After reading the last bar, clean the hole in the comparator base and read and record the reference-bar indication.9.4.1.
49、2 When the required strength of the mortar is achieved in accordance with 9.2, store the bars in fresh sulfate solution. Atsubsequent readings for length change, proceed as described in 9.4.1.1; cleaning the socket in the base of the comparator beforereading the reference bar initially and after reading each mortar bar. Record reference bar and mortar bar readings. Read and recordthe reference bar again after measurement of the last bar. Blot only around the pins (Note 7). Return each bar to the used sulfatesolution after
