1、Designation: C 1012 04Standard Test Method forLength Change of Hydraulic-Cement Mortars Exposed to aSulfate Solution1This standard is issued under the fixed designation C 1012; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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. Scope1.1 This test method covers the determination of lengthchange of mortar bars immersed in a sulfate solution. Mortar
3、bars made using mortar described in Test Method C 109/C 109M are cured until they attain a compressive strength of20.0 6 1.0 MPa (3000 6 150 psi), as measured using cubesmade of the same mortar, before the bars are immersed.1.2 The values stated in SI units are to be regarded as thestandard. The val
4、ues shown in parentheses are for informationpurposes only.1.3 This standard does not purport to address all of thesafety concerns, 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-bil
5、ity of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 109/C 109M Test Method for Compressive Strength ofHydraulic Cement Mortars (Using 2-in. or 50mm CubeSpecimens)C 114 Test Method for Chemical Analysis of HydraulicCementC 150 Specification for Portland CementC 157
6、/C 157M Test Method for Length Change of Hard-ened Hydraulic-Cement, Mortar, and ConcreteC 215 Test Method for Fundamental Transverse, Longitu-dinal, and Torsional Frequencies of Concrete SpecimensC 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC 348
7、Test Method for Flexural Strength of HydraulicCement MortarsC 349 Test Method for Compressive Strength of HydraulicCement Mortars (Using Portions of Prisms Broken inFlexure)C 452 Test Method for Potential Expansion of Portland-Cement Mortars Exposed to SulfateC 490 Practice for Use of Apparatus for
8、the Determinationof Length Change of Hardened Cement Paste, Mortar, andConcreteC 511 Specification for Mixing Rooms, Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in theTesting of Hydraulic Cements and ConcretesC 595 Specification for Blended Hydraulic CementsC 597 Test Method for Pulse V
9、elocity Through ConcreteC 618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use as a Mineral Admixture inConcreteC 684 Test Method for Making, Accelerated Curing, andTesting Concrete Compression Test SpecimensC 778 Specification for Standard SandC 917 Test Method for Evaluat
10、ion of Cement StrengthUniformity From a Single SourceC 989 Specification for Ground Granulated Blast-FurnaceSlag for Use in Concrete and MortarsD 1193 Specification for Reagent WaterE 18 Test Methods for Rockwell Hardness and RockwellSuperficial Hardness of Metallic Materials2.2 American Concrete In
11、stitute Reports:ACI C201-2R-01 Guide to Durable Concrete33. Significance and Use3.1 This test method provides a means of assessing thesulfate resistance of mortars made using portland cement,blends of portland cement with pozzolans or slags, and blendedhydraulic cements. Method C 452 is suitable for
12、 evaluatingportland cements but not blended cements or blends of portlandcement with pozzolans or slags.3.2 The standard exposure solution used in this test method,unless otherwise directed, contains 352 moles of Na2SO4perm3(50 g/L). Other sulfate concentrations or other sulfates suchas MgSO4may be
13、used to simulate the environmental exposureof interest. Further discussion of these and other technicalissues is given in the Appendix.1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.29 on Sulfate Resistance.Current edit
14、ion approved Jan. 1, 2004. Published February 2004. Originallyapproved in 1984. Last previous edition approved in 2003 as C 1012 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inform
15、ation, refer to the standards Document Summary page onthe ASTM website.3Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Apparatus4.1 Mixer,
16、 conforming to the requirements of PracticeC 305.4.2 Cube Molds, conforming to the requirements of TestMethod C 109/C 109M.4.3 Bar Molds, conforming to the requirements of Specifi-cation C 490.4.4 Comparator, conforming to the requirements of Speci-fication C 490.4.5 ContainersThe containers in whic
17、h the bars are im-mersed shall be corrosion resistent such as plastic, glass, orceramic. Support the bars so that no end or side of a bar restsagainst the container. Seal the container with a lid so that thesulfate solution cannot evaporate.4.6 Curing Tank, conforming to the requirements of TestMeth
18、od C 684.5. Reagents and Materials5.1 Purity of ReagentsUSP or technical grade chemicalsmay be used, provided it is established that any reagent used isof sufficiently high purity to permit its use without lesseningthe accuracy of the determination. When tests are made that areexpected to produce re
19、sults that are close to an acceptance-rejection value, it is recommended that reagent grade chemi-cals be used. Such chemicals shall conform to the specifica-tions of the Committee on Analytical Reagents for theAmerican Chemical Society where such specifications areavailable.45.2 Purity of WaterUnle
20、ss otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Type IV of Specification D 1193.5.3 Sodium Sulfate (Na2SO4)Check the water content byloss on ignition each time the solution is prepared. Anyanhydrous or hydrated sodium sulfate may be used if the water
21、content of the salt is checked by loss on ignition and propercorrections made to account for the specified sulfate concen-tration.5.4 Sulfate SolutionEach litre of solution shall contain50.0gofNa2SO4dissolved in 900 mL of water, and shall bediluted with additional distilled or deionized water to obt
22、ain1.0 L of solution. Mix the solution on the day before use, cover,and store at 23.0 6 2.0C (73.5 6 3.5F). Determine the pH ofthe solution before use; reject the solution if the pH range isoutside 6.0 to 8.0. Maintain the volume proportion of sulfatesolution to mortar bars in a storage container at
23、 4.0 6 0.5volumes of solution to 1 volume of mortar bars. For mortarbars1by1by1114 in. (volume of 184 mL or 11.25 in.3), thisis 645 to 830 mL of solution per mortar bar in the storagecontainer. For mortar bars 25 by 25 by 285 mm (volume 178mL), this is 625 to 800 mL of solution per mortar bar in the
24、storage container.5.5 Materials:5.5.1 Graded Standard Sand, as specified in SpecificationC 778.5.5.2 Stainless Steel Gage Studs, as specified in Specifica-tion C 490.6. Hazards6.1 WarningFresh hydraulic cementitious mixtures arecaustic and may cause chemical burns to skin and tissue uponprolonged ex
25、posure.57. Preparing Mortars7.1 Make mortars as described in Test Method C 109/C 109M, that is, 1 part cement to 2.75 parts of sand by mass.Use a water-cement ratio by mass of 0.485 for all non-air-entraining portland cements and 0.460 for all air-entrainingportland cements. Use a water-cement ratio
26、 by mass of 0.485for non-air-entraining portland-pozzolan (IP) and portland-blast furnace slag (IS) cements. For blends of portland cementwith a pozzolan or slag, use a water-cement ratio that developsa flow within 65 of that of the portland-cement mortar at awater-cement ratio of 0.485.8. Specimen
27、Molds8.1 Prepare the specimen molds in accordance with therequirements of Specification C 490 except the interior sur-faces of the mold shall be covered with a release agent. Arelease agent will be acceptable if it serves as a parting agentwithout affecting the setting of the cement and without leav
28、ingany residue that will inhibit the penetration of water into thespecimen.NOTE 1TFE-fluorocarbon tape complies with the requirements for amold release agent.9. Procedure9.1 Molding and Initial Curing of SpecimensMold the testbars in accordance with Test Method C 157/C 157M. Mold thecubes in accorda
29、nce with Test Method C 109/C 109M. A set ofspecimens to test one cement consists of 6 bars and up to 21cubes (Note 2). Immediately after molding, cover the moldswith a rigid steel, glass, or plastic plate, seal the plate to themold so as to be watertight, and place the mold in the curingtank in wate
30、r at 35 6 3C (95 6 5F) for 2312 h 6 30 min, asin Test Method C 684, Procedure A (Warm-Water Method).Place the sealed molds in the curing tank with the bottom of thebars as cast down, that is, in the same relative position in whichthe bars were cast. At 2312 h 6 30 min, remove molds fromtank and demo
31、ld the specimens.NOTE 2The set of cubes consists of 21 cubes to be tested as describedherein when significant information on the strength development rate isnot available. When information is available (as for example, from the useof the procedures of Test Method C 917) that would justify making few
32、ercubes, only those needed to confirm the time the mortar achieves 20.0 61.0 MPa (3000 6 150 psi) are needed.9.2 Subsequent Curing and Preparation for TestAfterdemolding, store all bars and cubes, except the two to be4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Soci
33、ety, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.
34、5See Manual of Cement Testing, Section on Safety, Annual Book of ASTMStandards, Vol 04.01.C1012042broken, in a curing tank of saturated limewater at 23.0 6 2.0C(73.5 6 3.5F). Break two cubes in compression in accordancewith Test Method C 109/C 109M after demolding when thespecimens have cooled to am
35、bient temperature under moistcloths. If the mean strength of the two cubes is 20 MPa (2850psi) or more, observe and record comparator readings inaccordance with Specification C 490 and as prescribed in thesection on Measurements of Length Change and place all thebars in the sulfate solution. If 20 M
36、Pa (2850 psi) is notachieved, store the demolded cubes and mortar bars in thecuring tank and test additional cubes. Predict from the first twocubes when a compressive strength of at least 20 MPa (2850psi) will be reached. Verify the prediction, and at that timeobserve and record comparator readings
37、and place all the barsin the sulfate solution (Note 3). This measurement is desig-nated as the initial length. The storage temperature and testtemperature shall be 23.0 6 2.0C (73.5 6 3.5F).NOTE 3If the value for strength at 24 h is less than 20.0 MPa (2850psi) and additional testing on the same day
38、 is not possible, or, is unlikelyto yield a 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 thebatch.9.3 Storage of Test Bars during Exposure to Test SolutionCover the container of the bars and test solution, and
39、seal it toprevent evaporation from the inside, or dilution with waterfrom the outside. (See Note 4.) The storage temperature andtest temperature shall be 23.0 6 2.0C (73.5 6 3.5C). (SeeNote 5.)NOTE 4Gaffers tape or duct tape has been found to be suitable forsealing the container.NOTE 5This is the sa
40、me temperature and temperature range as thatspecified for moist rooms in Specification C 511.9.4 Measurements of Length ChangeAt 1, 2, 3, 4, 8, 13,and 15 weeks after the bars are placed in the sulfate solution,test them for length change using the length comparator inaccordance with Specification C
41、490. Review the data at 15weeks. Make the subsequent measurements at a minimum of 4,6, 9, and 12 months. If at any time the rate of change betweenreadings is great, insert other readings as needed to ensure theintervals are short enough to permit observing and reportingthe behavior of the bars. If c
42、ompliance with ACI C201-2R-01Class 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 3exposure.9.4.1 Details of Measurement of Bars for Length Change:9.4.1.1 Clean the hole in the base of the comparator intowh
43、ich the gage stud on the lower end of the bar fits (this holetends to collect water and sand and should be cleaned afterevery reading). Read and record the comparator indication ofthe length of the reference bar. Take one bar out of immersion,blot the pins, put the bar in the comparator, read, and r
44、ecord theindication. Return the bar to immersion and clean the hole inthe base of the comparator. Take out the second bar and treat itin a like manner. Return the second bar to immersion, recordthe reading, and clean the hole in the base of the comparator.Continue the procedure until all bars have b
45、een read, returnedto immersion, and the readings recorded, cleaning the hole inthe bottom of the comparator each time. After reading the lastbar, clean the hole in the comparator base and read and recordthe reference-bar indication.9.4.1.2 When the required strength of the mortar is achievedin accor
46、dance with 9.2, store the bars in fresh sulfate solution.At subsequent readings for length change, proceed as describedin 9.4.1.1; cleaning the socket in the base of the comparatorbefore reading the reference bar initially and after reading eachmortar bar. Record reference bar and mortar bar reading
47、s. Readand record the reference bar again after measurement of the lastbar. Blot only around the pins (Note 7). Return each bar to theused sulfate solution after reading. When all the bars have beenmeasured, discard the used solution. Rinse the container oncewith water, pouring out water and debris.
48、 Replace the frameholding the bars in the container, fill the container with enoughnew sulfate solution to immerse bars, and secure the lid on thecontainer.NOTE 7The purpose of the minimal blotting of the pins and noblotting of the bars is to avoid drying and shrinkage of the bars. It has beenobserv
49、ed that if the pins are blotted, and the bar placed in the comparatorand the dial read, and the bar is then wiped gently with a dry cloth, the barwill shrink measurably. Therefore, drying should be minimized.9.4.2 Examination of Specimens After Measuring LengthChangeWhen the bars seem to have behaved in an unusualway or when the test is part of a research study, test thespecimens for warping by placing them on a plane surface sothat the ends are curved down and the maximum bowingmeasured. Note cracking (presence, location, type); also notesurface depos
