1、Designation: C452/C452M 10Standard Test Method forPotential Expansion of Portland-CementMortars Exposed to Sulfate1This standard is issued under the fixed designation C452/C452M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the
2、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.1. Scope*1.1 This test method, which is applicable only to portlandcements, covers the determination of the expansion of m
3、ortarbars 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 either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equ
4、ivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard. Values in SI units or inch-pound units shallbe obtained by measurement in SI units or inch pound unitsor by appropriate conversion, using the
5、 Rules for Conversionand Rounding given in IEEE/ASTM SI 10, of measurementsmade in other units or SI units. Values are stated in only SIunits when inch-pound units are not used in practice.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is
6、 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 skin and tissue uponprolonged exposu
7、re.22. Referenced Documents2.1 ASTM Standards:3C109/C109M Test Method for Compressive Strength ofHydraulic Cement Mortars (Using 2-in. or 50-mm CubeSpecimens)C150 Specification for Portland CementC230/C230M Specification for Flow Table for Use in Testsof Hydraulic CementC305 Practice for Mechanical
8、Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC471M Test Methods for Chemical Analysis of Gypsumand Gypsum Products (Metric)C490 Practice for Use of Apparatus for the Determinationof Length Change of Hardened Cement Paste, Mortar, andConcreteC511 Specification for Mixing Rooms,
9、Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in theTesting of Hydraulic Cements and ConcretesC778 Specification for SandC1005 Specification for Reference Masses and Devices forDetermining Mass and Volume for Use in the PhysicalTesting of Hydraulic CementsD1193 Specification for Reagent W
10、aterIEEE/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 portland cement. This test method is also
11、used toestablish that a sulfate-resisting portland cement meets theperformance requirements of Specification C150.4. Apparatus4.1 Weights and Weighing Devices, conforming to the re-quirements of Specification C1005.4.2 Flow Table, conforming to the requirements of Specifi-cation C230/C230M.4.3 Mixer
12、, Bowl, and Paddle, conforming to the require-ments of Practice C305.1This 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 June 1, 2010. Published July 2010. Originally approve
13、din 1960. Last previous edition approved in 2006 as C45206. DOI: 10.1520/C0452_C0452M-10.2Section 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
14、 Annual Book of ASTMStandards volume information, refer to the standards 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.4.4 T
15、rowel and Tamper, conforming to the requirements ofTest Method C109/C109M.4.5 Glass Graduates, Molds, and Length Comparator, con-forming to the requirements of Practice C490.5. Temperature and Humidity5.1 Molding Room, Dry Materials, and Mixing WaterMaintain the temperature of the molding room, dry
16、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 requirementsof Specification C511.6. Materials6.1 Use graded sand that conforms to Specification C778Table 1 Standard Sand Requirement
17、s 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 cement and gypsum requir
18、ed 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 SO3content of the gypsum
19、 is unknown, analyzethe gypsum for SO3content using Test Methods C471M.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 D1193.7. Number and Dimensions of Test Specimens7.1 Make six
20、 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-in.specimens govern.8. Prepari
21、ng Specimen Molds8.1 Prepare the molds in accordance with Practice C490.9. 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 184 mL of mixing water forall ai
22、r-entraining portland cements.9.2 Mix the mortar according to the procedure for mixingmortars of Practice C305, except after placing the mixing waterin the bowl, add the gypsum and mix at the slow speed for 15s, then stop the mixer, add the cement, and continue asprescribed in Practice C305.10. Proc
23、edure10.1 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 from themixer and shake the excess
24、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 the top layerhas been compacted, cut
25、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 from the molds, properly identify, and
26、 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 the specimens withat least 6-mm 14-in. cle
27、arance on all sides except for thenecessary supports. Cover the specimens with at least 13 mm12 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 7 days for the first28 days and every 28 day
28、s 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 min fromthe time the cement and water are mixed
29、 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 the difference in length of the specimen at 2
30、4h 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 the number of the remaining specimens, asfollo
31、ws:No. of Specimens Maximum Permissible Range, %3 0.01040.14The sole source of supply of the apparatus known to the committee at this timeis TerraAlba No. 1, available from the U.S. Gypsum Co., Southard, OK plant. If youare aware of alternative suppliers, please provide this information to ASTMInter
32、national Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.C452/C452M 1025 0.0126 0.01213. Report13.1 Report the average of the specimens comprising the setto the nearest 0.001 %.14. Precision and Bias14.1 Precisio
33、n:14.1.1 The single-operator standard deviation has beenfound 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 %.14.1.2 The multilaboratory standard de
34、viation 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 test method has been evaluatedby cooperat
35、ive 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 useful information on details of cement t
36、est 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,C45206, that may impact the use of this test met
37、hod. (Approved June 1, 2010)(1) Revised the standard as a dual units test method.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 determination of the va
38、lidity 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 or withdrawn. Your co
39、mments 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 that your comments hav
40、e 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 reprints (single or multiple
41、 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C01-1004.C452/C452M 103
