ASTM C563-2018 Standard Guide for Approximation of Optimum SO3 in Hydraulic Cement.pdf

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1、Designation: C563 17C563 18Standard Guide forApproximation of Optimum SO3 in Hydraulic Cement1This standard is issued under the fixed designation C563; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu

2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This guide describes the determination of approximate optimum SO3 for maximum performance as a result of substitutingcalcium sulfate for

3、 a portion of the cement.1.2 This guide refers to the sulfur trioxide (SO3) content of the cement only. Slag cements and occasionally other hydrauliccements can contain sulfide or other forms of sulfur. The determination of SO3 content by rapid methods may include these otherforms, and may therefore

4、 produce a significant error. If a significant error occurs, analyze the cement for SO3 content using thereference test method of Test Methods C114 for sulfur trioxide.1.3 Values stated as SI units are to be regarded as standard.1.4 This standard does not purport to address all of the safety concern

5、s, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance

6、 with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standar

7、ds:2C39/C39M Test Method for Compressive Strength of Cylindrical Concrete SpecimensC78C78/C78M Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading)C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or 50-mm Cube Specimens)C1

8、14 Test Methods for Chemical Analysis of Hydraulic CementC150C150/C150M Specification for Portland CementC192C192/C192M Practice for Making and Curing Concrete Test Specimens in the LaboratoryC204 Test Methods for Fineness of Hydraulic Cement by Air-Permeability ApparatusC305 Practice for Mechanical

9、 Mixing of Hydraulic Cement Pastes and Mortars of Plastic ConsistencyC430 Test Method for Fineness of Hydraulic Cement by the 45-m (No. 325) SieveC465 Specification for Processing Additions for Use in the Manufacture of Hydraulic CementsC471M Test Methods for Chemical Analysis of Gypsum and Gypsum P

10、roducts (Metric)C595C595/C595M Specification for Blended Hydraulic CementsC596 Test Method for Drying Shrinkage of Mortar Containing Hydraulic CementC1157C1157/C1157M Performance Specification for Hydraulic CementC1437 Test Method for Flow of Hydraulic Cement MortarC1679 Practice for Measuring Hydra

11、tion Kinetics of Hydraulic Cementitious Mixtures Using Isothermal CalorimetryC1702 Test Method for Measurement of Heat of Hydration of Hydraulic Cementitious Materials Using Isothermal ConductionCalorimetry3. Significance and Use3.1 The purpose of this guide is to estimate the SO3 content for a hydr

12、aulic cement that gives maximum performance. The valueobtained is one way to establish an appropriate level of sulfate in the manufacture of cements specified in SpecificationsC150C150/C150M, C595C595/C595M, and C1157C1157/C1157M.1 This guide is under the jurisdiction of ASTM Committee C01 on Cement

13、 and is the direct responsibility of Subcommittee C01.28 on Sulfate ContentCurrent edition approved Feb. 1, 2017Oct. 15, 2018. Published March 2017October 2018. Originally approved in 1965. Last previous edition approved in 20162017 asC563 16.C563 17. DOI: 10.1520/C0563-17.10.1520/C0563-18.2 For ref

14、erencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide

15、the user of an 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 stan

16、dard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 The SO3 content of a cement giving maximum perfor

17、mance is different at different ages, with different performance criteriaand with different materials such supplementary cementitious materials and chemical admixtures. A manufacturer can choose theperformance criteriato determine optimum SO3 content. This optimum SO3 content may be a compromise bet

18、ween different agesand different performance criteria.NOTE 1Typically, the optimum SO3 content is higher the later the age.3.3 This guide indicates optimum SO3 content for cement in mortar made and cured at a standard temperature of 23.0 6 2.0C(73.5 6 3.5F). The optimum SOcement, optionally in prese

19、nce of supplementary cementitious materials and admixtures. Severalalternate methods are allowed: compressive strength of concrete or mortar, heat of hydration of paste or3 increases with increasingtemperature and may increase when water-reducing admixtures are used.mortar, and drying shrinkage of m

20、ortar.3.4 It should not be assumed that the optimum SO3 estimated in this guide is the same SO3 content for optimum performanceof a concrete prepared from the cement.in the field using the same materials. The optimum SO3 is influenced by parameters suchas ambient and fresh concrete temperature, admi

21、xtures, and supplementary cementitious materials.3.5 The guide is applicable to cements specified in Specifications C150C150/C150M, C595C595/C595M, and C1157C1157/C1157M.4. Apparatus4.1 Use the apparatus as specified in Test Methods C109/C109M, C192C192/C192M, C596, or C1702.5. Materials5.1 Calcium

22、SulfateUse calcium sulfate for addition to the cement that is either a high-grade natural gypsum having an SO3content of at least 46 %, or the calcium sulfate from the source used for the intended plant production. Grind the calcium sulfateto 100 % passing the 75-m (No. 200) sieve, and at least 800

23、m2/kg Blaine fineness (Test Method C204). If the SO3 content ofthe calcium sulfate is unknown, analyze it in accordance with Test Methods C471M.NOTE 2The calcium sulfate source can impact the optimum sulfate result due in part to differences in surface area and form of the calcium sulfate(for exampl

24、e, gypsum, calcium sulfate hemi-hydrate, or anhydrous calcium sulfate). Temperatures in cement finish mills during production can reachlevels to partially or completely change the form of calcium sulfate in cement.cement, while laboratory grinding of calcium sulfate may alter its reactivitythrough i

25、ncreased fineness and partial change of the form of the calcium sulfate. Different clinkers may react differently to the effect of sulfate forms.In particular, if the dissolution rate of sulfate during cement hydration is at any time lower than the sulfate consumption rate of the aluminates, the sul

26、fatein solution may become temporarily depleted, resulting in elevated aluminate reactivity and significant reductions in alite reactivity. Elevated aluminatereactivity may lead to loss of workability and admixture performance as well as reduced rate of strength development and setting behavior that

27、 has arelatively low degree of repeatability and reproducibility. On the other hand, if the dissolution rate of sulfate before placing of concrete is higher thanthe sulfate consumption rate of the aluminates, precipitation of secondary gypsum may cause loss of workability and false set.5.2 CementMak

28、e cements of different sulfate levels at a single production site. Make the cements so that the amount ofcalcium sulfate added, and the subsequent dilution effects, are the only difference in constituent materials.5.2.1 Grind samples to a fineness within 13 m/kgm2/kg of the other samples when tested

29、 in accordance with Test Method C204.Since calcium sulfate sources are typically softer than clinker, an adjustment of 10 m2/kg for every 1 % calcium sulfate additionis permitted, as shown in equation Eq 1.FA,X 5FM,X 210SO3,X 2 SO3,median!SO3,CS 100(1)where:SO3,CS = percentage of SO3 in the calcium

30、sulfate,SO3,median = SO3 percentage of the sample with the median SO3 of the samples tested,SO3,X = SO3 percentage of cement sample X,FM,X = measured fineness of cement sample X, andFA,X = adjusted fineness of cement sample X.NOTE 3Differences in the mill conditions between samples of different sulf

31、ate levels should be minimized. For this reason samples are normally takenduring the same production campaign. Strategies should be employed to minimize the differences in fineness of the clinker when taking samples, suchas targeting a specific sieve size range and adjusting around that target withi

32、n reasonable tolerances. Since calcium sulfate is softer, and thus easier togrind than clinker, increases in calcium sulfate content will elevate the fineness of the cement without a change in the grinding energy or the finenessof the clinker.NOTE 4As an example, consider the case of one cement samp

33、le with an SO3 content of 2.7 % and a fineness of 380 m2/kg, which is the sample withthe median SO3 content, and another sample with an SO3 content of 3.7 % and a fineness of 405 m2/kg. The second sample has a 1.0% higher SO3 content,or 2.2 % more calcium sulfate addition, assuming the calcium sulfa

34、te was 45 % SO3. The adjusted cement fineness of the second sample would be reducedby 22 m2/kg (10 2.2) to 383 m2/kg by using Equation Eq 1 as shown in Eq 2. This value of 383 m2/kg is within 13 m2/kg of the fineness of 380 m2/kg,and thus is acceptable for testing.FA,X 54052103.7 2 2.7!451005383 m2k

35、g (2)C563 1825.2.2 Determine the percentage of the following analytes by Test Method C114 for each cement tested: silicon dioxide (SiO2),aluminum oxide (Al2O3), ferric oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), sulfur trioxide (SO3), loss onignition, insoluble residue, sodium oxide (

36、Na2O), and potassium oxide (K2O). Calculate the potential percentages of the followingcompounds for portland cements according to Specification C150C150/C150M: tricalcium silicate, dicalcium silicate, tricalciumaluminate, and tetracalcium aluminoferrite. When applicable, report the amount of limesto

37、ne and Specification C465 inorganicprocessing additions according to Specification C150C150/C150M. Determine the fineness of each cement tested according to TestMethods C204 and C430.NOTE 5The amount of material retained on the 45-m sieve has been used as an indication of the clinker fineness. When

38、high efficiency separatorsare used, the amount retained on a 20-m sieve has also been used as an indicator of clinker fineness.6. Procedure6.1 Sulfate Levels to TestTest at least five different sulfate levels.6.1.1 SO3 contents are to be at least 0.20 % different unless more than five different SO3

39、contents are being tested. Themaximum and minimum SO3 content of the blended samples must differ by at least 2.0 % SO3 content.NOTE 6The same mixture design and materials shall be used when comparing different SO3 contents. Use one or more of the following test methodsto evaluate the performance:6.1

40、.1.1 When adding calcium sulfate it is considered as part of the mass of cement for proportioning.6.1.1.2 Use the following equation to calculate the total SO3 in the blended sample of cement and calcium sulfate:SO3-Total 5 Mcalcium sulfateMcalciumsulfate1Mcememnt3SO3-calcium sulfate1 McementMcalciu

41、msulfate1Mcement3SO3-cement (3)where:Mcalcium sulfate = the mass of the calcium sulfate,Mcement = the mass of the cement,SO3-cement sulfate = the percent by mass of SO3 in the calcium sulfate, andSO3-cement = the percent by mass of the SO3 in the cement.NOTE 7More sulfate levels may be tested to hel

42、p improve the precision of the interpretation of the results. Extremely high and low sulfate levelscan give results that deviate from the typical peak behavior which may need to be treated as outliers when using a mathematical fitting procedure.6.2 The same mixture design and materials shall be used

43、 when comparing different SO3 contents. Use one or more of thefollowing test methods to evaluate the performance:6.2.1 Mortar compressive strengthDetermine mortar compressive strength at each sulfate level at the age of 24 6 14 h, 3 days6 1 h, or 7 days 6 3 h in accordance with Test Method C109/C109

44、M except as follows:6.2.1.1 When mixing in accordance with the “Procedure for Mixing Mortars” section of Practice C305, add the calcium sulfateto the water, unless the calcium sulfate addition has been previously ground and mixed with the cement; then start the mixer andmix at slow speed (140 6 5 rp

45、m) for 15 s; then stop the mixer and add the cement to the water; then start the mixer and mix atslow speed (140 6 5 rpm) for 30 s.6.2.1.2 Use the amount of mixing water to produce a flow of 110 6 5 for one of the mixtures using 25 drops of the table asdetermined in the section on Procedures in Test

46、 Method C1437. Use that same amount of water (constant w/cm) for each mixturewith different sulfate levels.NOTE 8The mixture with the median sulfate level or lowest sulfate level is often used to determine the water content.6.2.2 Heat of hydrationDetermine heat of hydration at each sulfate level at

47、the age of 24 6 desired ages 14 h, 3 days 6 1 h,or 7 days 6 3 h in accordance with Test Method C1702 except as follows:6.2.2.1 Add the calcium sulfate to the water, unless the calcium sulfate addition has been previously ground and mixed withtheIf making calcium sulfate powder additions to an indust

48、rially produced cement sample, add the cement and calcium sulfatepowder directly into the calorimetry sample vial and dry mix the solids inside the calorimetry sample vial to ensure that the calciumsulfate is blended with the cement prior to water addition. If using industrially-produced cement samp

49、les with the calcium sulfateadditions already interground, follow the procedure forTest Method C1702cement; MethodAor B except as follows.Alternatively,produce a mortar as described 6.2.1.6.2.2.2 Additions of other materials typically used in concrete, such as supplementary cementitious materials and chemicaladmixtures, can be used.used, provided that the content of supplementary cementitious materials, chemical admixtures, or both arekept the same for each different mixture.6.2.2.3 Mortars are allowed to be used in addition to pastes. When testing