1、Designation: C 452 06Standard Test Method forPotential Expansion of Portland-CementMortars Exposed to Sulfate1This standard is issued under the fixed designation C 452; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st 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. Scope*1.1 This test method, which is applicable only to portlandcements, covers the determination of the expansion of mortarbars
3、 made from a mixture of portland cement and gypsum insuch proportions that the mixture has a sulfur trioxide (SO3)content of 7.0 mass %.1.2 The values stated in SI units (IEEE/ASTM SI-10) are tobe regarded as the standard.1.3 This standard does not purport to address all of thesafety concerns, if an
4、y, 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-bility of regulatory limitations prior to use.WarningFresh hydraulic cementitious mixtures are caus-tic and may cause chemical burns to ski
5、n and tissue uponprolonged exposure.22. Referenced Documents2.1 ASTM Standards:3C 109/C 109M Test Method for Compressive Strength ofHydraulic Cement Mortars(Using 2-in. or 50-mm CubeSpecimens)C 150 Specification for Portland CementC 230/C 230M Specification for Flow Table for Use in Testsof Hydrauli
6、c CementC 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC 471M Test Methods for Chemical Analysis of Gypsumand Gypsum Products MetricC 490 Practice for Use of Apparatus for the Determinationof Length Change of Hardened Cement Paste, Mortar, andConcret
7、eC511 Specification for Mixing Rooms, Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in theTesting of Hydraulic Cements and ConcretesC 778 Specification for SandC 1005 Specification for Reference Masses and Devices forDetermining Mass and Volume for Use in the PhysicalTesting of Hydraulic
8、CementsD 1193 Specification for Reagent WaterIEEE/ASTM SI-10 Practice for Use of the InternationalSystem of Units (SI): The Modern Metric System3. Significance and Use3.1 This test method is used primarily by those interested inresearch on methods for determining the potential sulfateresistance of p
9、ortland cement. This test method is also used toestablish that a sulfate-resisting portland cement meets theperformance requirements of Specification C 150.4. Apparatus4.1 Weights and Weighing Devices, conforming to the re-quirements of Specification C 1005.4.2 Flow Table, conforming to the requirem
10、ents of Specifi-cation C 230/C 230M.4.3 Mixer, Bowl, and Paddle, conforming to the require-ments of Practice C 305.4.4 Trowel and Tamper, conforming to the requirements ofTest Method C 109/C 109M.4.5 Glass Graduates, Molds, and Length Comparator, con-forming to the requirements of Practice C 490.5.
11、Temperature and Humidity5.1 Molding Room, Dry Materials, and Mixing WaterMaintain the temperature of the molding room, dry materials,and mixing water at 23.0 6 4.0 C (73.5 6 7 F) and therelative humidity of the molding room at not less than 50 %.5.2 Moist Cabinet or Room, conforming to the requireme
12、ntsof Specification C511.1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.29 on Sulfate Resistance.Current edition approved May 15, 2006. Published June 2006. Originallyapproved in 1960. Last previous edition approved in
13、2002 as C 452 02.2Section on Safety, Manual of Cement Testing, Annual Book of ASTMStandards, Vol 04.01.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards
14、 Document Summary page onthe ASTM website.1*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.6. Materials6.1 Use graded sand that conforms to Specification C 778Table 1 S
15、tandard Sand Requirements for making the testmortar.6.2 For the gypsum addition to portland cement, use highgrade natural gypsum4with 100 % passing the 150-m (No.100) sieve, at least 94 % passing the 75-m (No. 200) sieve,and at least 90 % passing the 45-m (No. 325) sieve. Calculatethe percentage of
16、cement and gypsum required to provide amixture containing 7.0 mass % SO3as follows:Cement, % 5 g 2 7.0!/g 2 c!# 3 100 (1)Gypsum, % 5 7.0 2 c!/g 2 c!# 3 100 (2)where:c =SO3content of the portland cement, %,g =SO3content of the gypsum, %, and7.0 = SO3content of the cement-gypsum mixture, %.6.3 If the
17、SO3content of the gypsum is unknown, analyzethe gypsum for SO3content using Test Methods C 471M.Determine the SO3content to the nearest 0.1 %.6.4 Purity of WaterUnless otherwise indicated, referencesto water mean reagent water conforming to Type IV ofSpecification D 1193.7. Number and Dimensions of
18、Test Specimens7.1 Make six 25 by 25 by 285-mm (or 1 by 1 by 1114-in.)test specimens, three from each of two batches, for eachcement.7.2 In routine tests, 25 by 25 by 160-mm (or 1 by 1 by614-in.) specimens may be used, but in case of dispute, resultsobtained with 25 by 25 by 285-mm (or 1 by 1 by 1114
19、-in.)specimens govern.8. Preparing Specimen Molds8.1 Prepare the molds in accordance with Practice C 490.9. Proportioning, Consistency, and Mixing of Mortar9.1 Use 400 g (cement plus gypsum) and 1100 g of sand foreach batch. Use 194 mL of mixing water for all non-air-entraining portland cements, and
20、 184 mL of mixing water forall air-entraining portland cements.9.2 Mix the mortar according to the procedure for mixingmortars of Practice C 305, except after placing the mixingwater in the bowl, add the gypsum and mix at the slow speedfor 15 s, then stop the mixer, add the cement, and continue aspr
21、escribed in Practice C 305.10. Procedure10.1 Molding Test Specimens:10.1.1 Immediately upon completion of the flow test, returnthe mortar to the bowl, scrape down into the batch any mortaron the side of the bowl, and remix at the medium speed (2856 10 r/min) for 15 s. Remove the paddle and the bowl
22、from themixer and shake the excess mortar from the paddle into thebowl. Fill the mold in two layers, each layer being compactedwith the tamper. Work the mortar into the corners, around thegage studs, and along the surfaces of the mold with the tamperuntil a homogeneous specimen is obtained. After th
23、e top layerhas been compacted, cut the mortar off flush with the top of themold and smooth the surface with a few strokes of the trowel.10.2 Storage of Test Specimens:10.2.1 Initial StorageCure the specimens in the molds inthe moist closet at 23 6 2 C (73.5 6 3.5 F) for 22 to 23 h.Then remove them f
24、rom the molds, properly identify, and placein water at 23 6 2 C (73.5 6 3.5 F) for at least 30 min priorto making the initial length measurement.10.2.2 Subsequent StorageAfter the bars have been re-moved from the molds and measured, store them horizontallyin water at 23 6 2 C (73.5 6 3.5 F). Store t
25、he specimens withat least 6-mm (14-in.) clearance on all sides except for thenecessary supports. Cover the specimens with at least 13 mm(12 in.) of water. Use a volume of water that does not exceed5 times the volume of the bars to prevent excessive leaching.Replenish the water with fresh water every
26、 7 days for the first28 days and every 28 days thereafter.11. Length Measurement11.1 Measure the specimens for length by means of thelength comparator. Remove them from the water storage, oneat a time, and wipe with a damp cloth before measuring.11.2 Make the first reading at the age of 24 h 6 15 mi
27、n fromthe time the cement and water are mixed together. Measure thespecimen again at the age of 14 days.NOTE 1Additional information of value may be obtained by returningthe specimen to water storage after the 14-day test and making additionalmeasurements at later ages.12. Calculation12.1 Calculate
28、the difference in length of the specimen at 24h and at 14 days to the nearest 0.001 % of the effective gagelength and report as the expansion of the specimen at thatperiod. All specimens remaining after 14 days must comprise aset having at least three specimens with a permissible rangedepending on t
29、he number of the remaining specimens, asfollows:No. of Specimens Maximum Permissible Range, %3 0.01040.15 0.0126 0.01213. Report13.1 Report the average of the specimens comprising the setto the nearest 0.001 %.14. Precision and Bias14.1 Precision:14.1.1 The single-operator standard deviation has bee
30、nfound to be: 0.003 % for expansions between 0.01 and 0.04 %.Therefore, results of two properly conducted tests by the sameoperator on the same material should not differ from each otherby more than 0.009 %.4The sole source of supply of the apparatus known to the committee at this timeis TerraAlba N
31、o. 1, available from the U.S. Gypsum Co., Southard, OK plant. If youare aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.C452062
32、14.1.2 The multilaboratory standard deviation has beenfound to be 0.005 % for expansions between 0.01 and 0.04 %.Therefore, results of two properly conducted tests on the samematerial in two different laboratories should not differ fromeach other by more than 0.014 %.14.1.3 The precision of this tes
33、t method has been evaluatedby cooperative testing.514.2 BiasSince there is no accepted reference materialsuitable for determining the bias for this test method, nostatement on bias is being made.15. Keywords15.1 calcium sulfate; expansion; gypsum; portland cement;sulfate resistanceFor additional use
34、ful information on details of cement test methods, reference may be made to the “Manual of CementTesting,” which appears in the Annual Book of ASTM Standards, Vol 04.01.SUMMARY OF CHANGESCommittee C01 has identified the location of selected changes to this test method since the last issue,C 452 06,
35、that may impact the use of this test method. (Approved May 15, 2006)(1) Revised 6.1.(2) Added keywords.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that d
36、etermination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved
37、 or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel
38、that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprin
39、ts (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: 0011004.C452063
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