1、Designation: C688 081Standard Specification forFunctional Additions for Use in Hydraulic Cements1This standard is issued under the fixed designation C688; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTESection 5.1 was corrected editorially in August 2013.1. Scope*1.1 This specification covers methods to investigate theeffectiveness of a mate
3、rial to beneficially change the propertiesof hydraulic cements when the material is incorporated duringmanufacture of the cement.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 The effect of additions in cement may marke
4、dly changeproperties other than those they are intended to modify. Thisspecification is designed to test for such changes. Table 1 setsforth values for those properties of cement pastes and mortarsthat would permit a judgment of the changes effected by anaddition. Likewise, Table 2 sets forth simila
5、r criteria forconcrete. Certain additions may be found effective for morethan one purpose as indicated in 3.1.4 and 3.1.5.2. Referenced Documents2.1 ASTM Standards:2C39/C39M Test Method for Compressive Strength of Cylin-drical Concrete SpecimensC78 Test Method for Flexural Strength of Concrete (Usin
6、gSimple Beam with Third-Point Loading)C109/C109M Test Method for Compressive Strength ofHydraulic Cement Mortars (Using 2-in. or 50-mm CubeSpecimens)C143/C143M Test Method for Slump of Hydraulic-CementConcreteC150 Specification for Portland CementC151 Test Method for Autoclave Expansion of Hydraulic
7、CementC157/C157M Test Method for Length Change of HardenedHydraulic-Cement Mortar and ConcreteC187 Test Method for Amount of Water Required for Nor-mal Consistency of Hydraulic Cement PasteC219 Terminology Relating to Hydraulic CementC226 Specification for Air-Entraining Additions for Use inthe Manu
8、facture of Air-Entraining Hydraulic CementC232 Test Methods for Bleeding of ConcreteC234 Test Method for Comparing Concretes on the Basis ofthe Bond Developed with Reinforcing Steel (Discontinued2000) (Withdrawn 2000)3C266 Test Method for Time of Setting of Hydraulic-CementPaste by Gillmore NeedlesC
9、403/C403M Test Method for Time of Setting of ConcreteMixtures by Penetration ResistanceC451 Test Method for Early Stiffening of Hydraulic Cement(Paste Method)C465 Specification for Processing Additions for Use in theManufacture of Hydraulic CementsC595 Specification for Blended Hydraulic CementsC596
10、 Test Method for Drying Shrinkage of Mortar Contain-ing Hydraulic CementC666/C666M Test Method for Resistance of Concrete toRapid Freezing and ThawingC845 Specification for Expansive Hydraulic CementC1157 Performance Specification for Hydraulic Cement3. Terminology3.1 Definitions:3.1.1 accelerating
11、additiona functional addition that ac-celerates the setting or early strength, or both, of concrete andmortar.3.1.2 retarding additiona functional addition that retardsthe setting of concrete and mortar.3.1.3 set-control additiona functional addition composedessentially of calcium sulfate in any hyd
12、ration state fromCaSO4to CaSO42H2O.3.1.4 water-reducing additiona functional addition usedto reduce the quantity of mixing water required to produceconcrete and mortar of a given consistency.1This specification is under the jurisdiction of ASTM Committee C01 onCement and is the direct responsibility
13、 of Subcommittee C01.20 on Additions.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 1971. Last previous edition approved in 2005 as C688 00(2005). DOI:10.1520/C0688-08.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer
14、Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyri
15、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.5 water-reducing and accelerating additiona func-tional addition that reduces the quantity of mixing waterrequired to produce concrete of a given consistency and thataccelerates the settin
16、g or early strength development, or both,of concrete and mortar.3.1.6 water-reducing and retarding additiona functionaladdition that reduces the quantity of mixing water required toproduce concrete and mortar of a given consistency andsimultaneously retards the setting of concrete and mortar.NOTE 1T
17、his section is intended to provide a specification that may beapplied to calcium sulfates as defined in Terminology C219.NOTE 2It should be realized that some calcium sulfates, particularlysome byproduct calcium sulfates, have produced cements with undesiredset behavior after storage.4. Ordering Inf
18、ormation4.1 The purchaser shall specify the type of functionaladdition desired.5. Materials5.1 CementsThe cements used in the evaluation of theaddition shall be as described in Section 3.1, Cements, ofSpecification C465 with the following exceptions:5.1.1 At least one of the Type I cements shall con
19、tain notless than 9 percent tricalcium aluminate (C3A).5.1.2 Disregard the last sentence of Section 3.1.6 of Speci-fication C465 and substitute the following: “ Each controlcement shall comply with all the requirements in the specifi-cation (C150, C595, C845, and C1157) applicable to that typeof cem
20、ent. The method shall be adequate for the qualitative andquantitative determination of the addition in the finishedcement, and shall be fully described in the report of the tests onthe addition.”5.2 AggregatesThe aggregates used in the evaluation ofthe addition shall be in accordance with the Aggreg
21、ates portionof the Materials section of Specification C465, using propor-tions specified in Concrete Mixtures section of that specifica-tion.6. General Requirements6.1 The cement, mortar, and concrete in which each of theadditions is used shall conform to the respective requirementsprescribed in Tab
22、le 1 and Table 2, except that if the test cementfails to meet the requirements of Table 1, but possesses all therequirements listed in Table 2, then the requirements of Table2 shall govern approval of the addition.6.2 The trade name, source, and character of the materialshall be specified and the me
23、ans for the quantitative determi-nation of the proposed addition in the finished cement, shall beTABLE 1 Criteria for Evaluating Neat Cement and Mortar Containing Functional Cement AdditionsTestsType of AdditionWater Reducing Retarding AcceleratingWater-Reducingand RetardingWater-Reducing andAcceler
24、atingSet-ControlNormal consistency, deviation from control,percentage pointsA1.0 min +1.0 max +1.0 max 1.0 min 1.0 mm 1.0 maxStandard consistency (flow) deviation fromcontrol, percentage pointsA4.0 min +2.0 max +2.0 max 4.0 min 4.0 min 2.0 maxSetting time, (Gillmore) deviation from control,h:minInit
25、ialAt least . 1:00 laterB1:00 laterB.Not more than 1:00 earlier 3:30 later 1:30 earlier 3:30 later 1:30 earlier 1:00 earliernor nor nor nor1:30 later 1:30 later 1:30 later 1:30 laterSetting time, Vicat InitialCAt least . 0:50 laterB. . .Not more than 0:50 earlier 2:50 later 1:15 earlier 0:50 laterB1
26、:15 earlier 0:50 earliernor nor nor nor1:15 later 1:15 later 2:50 later 1:15 later 1:15 laterFinalNot more than 1:00 earlier 3:30 later 1:00 earlier 3:30 later 1:00 earlier 1:00 earliernor nor nor nor1:30 later 1:30 later 1:30 later 1:30 laterCompressive strength, min, percent of control:D1 day in m
27、oist air 110 90 125E90 125F1 day in moist air, 2 days in water 110 90 125E100 1251 day in moist air, 6 days in water 110 90 100 110 1101 day in moist air, 27 days in water 110 95 95 110 110Autoclave Expansionmax increase in % change in length comparedto control0.10 0.10 0.10 0.10 0.10 0.10Drying Shr
28、inkage of Mortarmax % change in length compared to control 0.020 0.020 0.030 0.020 0.020 0.020AThe minus sign indicates that the percentage of water required shall be less than that of the control cement by at least the indicated percentage points.BOr 50 % later, whichever is the lesser.CEither Vica
29、t or the Gillmore time of setting method shall be used at the choice of the manufacturer.DThe compressive strength of mortar containing the test cement shall be not less than 95 % of that attained at any previous test age. The objective of this limit is to requirethat the strength of mortar containi
30、ng the addition under test shall not decrease with age.EIn cases where the accelerated set time only is required, the strength can be reduced to 100 % of the control.FThe grand average of the 1, 3, 7, and 28-day strengths shall be not less than 95 % of the grand average for the corresponding control
31、 cement.C688 0812furnished by the manufacturer or seller of the addition, and theresults of such pertinent quantitative analysis shall form a partof the record of tests of the addition.6.3 At the request of the purchaser of an addition for aspecific functional purpose, the manufacturer shall state i
32、nwriting the content of any substance which is known to orbelieved to impair other desirable properties of the cement orconcrete.6.4 The additions shall be evaluated by comparing cementscontaining the “test addition” to cements ground from similarclinkers from the same source. Those cements without
33、testadditions are referred to in this specification as “controlcements.”6.4.1 Special Provisions for Set-Control Additions Con-forming to 3.1.3:6.4.1.1 The additions shall be evaluated by comparingcements containing the “test addition” to control cementsground from similar clinkers from the same sou
34、rce and underthe same grinding conditions with the mill temperatures beingwithin 6 3 C (5 F) of the same value. The control cementsshall be produced with calcium sulfate at any hydration statehaving a past record of satisfactory usage as an addition forportland cement.6.4.1.2 Each test cement shall
35、contain sufficient test additionCaSO4to produce a sulfur trioxide (SO3) content that differs byno more than 0.24 percentage points from that of the controlcement. The SO3shall be expressed as a percentage of the massof the cement and reported to the nearest 0.01 %.6.4.1.3 The test cements containing
36、 the additions shallconform to the requirements of 8.1 and Table 1. The cementsneed not be tested in concrete according to the requirements of8.2 and Table 2.6.5 The amount of addition that is incorporated into thecement for evaluation purposes shall be such as to produce thedesired effects as liste
37、d in Table 1. When these tests showcompliance with the requirements of this specification, theTABLE 2 Criteria for Evaluating Concrete Containing Functional Cement AdditionsATestsType of AdditionWater Reducing Retarding AcceleratingWater-Reducingand RetardingWater-Reducingand AcceleratingWater conte
38、nt, max, percent of control 95 . . 95 95Time of setting, (penetration) deviation fromcontrol, h:min:InitialAt least . 1:00 laterB1:00 laterBNot more than 1:00 earlier 3:30 later 3:30 earlier 3:30 later 3:30 earliernorFinal 1:00 laterNot more than 1:00 earlier 3:30 later . 3:30 later .nor1:30 laterCo
39、mpressive strength, min, percent ofcontrol:C1 dayD110 85 125E100 1253 days 110 85 125E100 1257 days 110 90 100 110 11028 days 110 90 95 110 1103 months 100 90 95 100 1001 year 100 90 95 100 100Flexural strength, min, percent ofcontrol:C1 dayD100 85 110 90 1103 days 100 85 110 100 1107 days 100 90 10
40、0 100 10028 days 100 90 90 100 1003 months 100 90 90 100 1001 year 100 90 90 100 100Bond strength, percent of control:28 days 100 90 100 100 100Volume change, expressed as change inlength, max, increase over control,percentage points:28 days 0.010 0.010 0.030 0.010 0.0103 months 0.010 0.010 0.030 0.
41、010 0.0101 year 0.010 0.010 0.030 0.010 0.010Durability factor, min, percent of controlF80 80 80 80 80AThe values in the table are intended to allow for normal variation in test results. For example, the object of the 90 % compressive strength requirement for a retardingaddition is to require a leve
42、l of performance comparable to that of the reference concrete.BOr 50 % later, whichever is the lesser.CThe compressive and flexural strength of the concrete containing the addition under test at any test age shall be not less than 90 % of that attained at any previous testage. The objective of this
43、limit is to require that the compressive or flexural strength of the concrete containing the addition under test shall not decrease with age.DOne-day strengths applicable only to Type III cement. One-year strength tests shall be made; however, the addition may be approved after completion of the 3-m
44、onthstrength results, at the discretion of the purchaser.EIn cases where the accelerated set time only is required, the strength can be reduced to 100 % of the control.FThis requirement is applicable only when the addition is to be used in air-entrained concrete.C688 0813addition shall be used only
45、in amounts up to the maximumamount tested in any one of the five cements used in theevaluation. For a cement requiring more than the establishedamount, a separate compliance test on this one cement can bemade which will then establish the new maximum amountwhich can be used.6.6 The cement produced w
46、ith the functional additionsshown in Section 3 shall comply with the specification for therespective cement and the ordinarily determined properties ofcement paste, mortar, or concrete made with the cementcontaining the test addition shall not differ from these sameproperties of the cement paste, mo
47、rtar, or concrete made withthe control cement as indicated by the standard tests, except asprovided in Table 1 and Table 2.6.7 Generally, the addition rates required for functionalpurposes are several times greater than those needed forprocessing purposes and the resultant increase in flowability, o
48、rlubricity, from these increased addition rates may cause suffi-cient reduction in mill retention time to affect significantly theparticle size distribution of the treated cement. The testaddition may, in instances where the full-scale tests haveshown reduced mill retention time to be significant, b
49、e deter-mined for acceptance purposes by making supplementarylaboratory or pilot batch mill grinds.6.8 Furthermore, the effect of the addition on the propertiesof the cement, mortar, or concrete shall be within the limits ofSection 8 and Table 1 and Table 2. In the event tests areconducted by making laboratory or pilot batch mill tests, thisfact shall be entered in the report as specified in Section 9, andthe specific tests shall be indicated.6.9 After it has been documented once by the test resultsthat a specific trade name and source of an addition ha