1、Designation: C688 14Standard 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.1. Scope*1.1 This specification covers methods to investigate theeffectiveness of a material to beneficially change the propertiesof hydraulic ceme
3、nts 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 markedly changeproperties other than those they are intended to
4、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 similar criteria forconcrete. Certain additions may be found effe
5、ctive for morethan one purpose as indicated in 3.1.4 and 3.1.5.2. Referenced Documents2.1 ASTM Standards:2C10/C10M Specification for Natural CementC39/C39M Test Method for Compressive Strength of Cylin-drical Concrete SpecimensC78 Test Method for Flexural Strength of Concrete (UsingSimple Beam with
6、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 HydraulicCementC157/C157M T
7、est 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 Manufacture of Air-Ent
8、raining 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Test Method for Comparing Concretes on the Basis ofthe Bond Developed with Reinforcing Steel (Discontinued2000) (Withdrawn 2000)3C266 Test Method for Time of Setting of Hydraulic-CementPaste by Gillmore NeedlesC403/C403M Test Met
9、hod 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 Test Method for D
10、rying 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 additiona function
11、al 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 hydration state fromC
12、aSO4to 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.3.1.5 water-reducing and accelerating additiona func-tional addition that reduces the quantity of mixing water1This specificati
13、on is under the jurisdiction of ASTM Committee C01 onCement and is the direct responsibility of Subcommittee C01.20 on Additions.Current edition approved Feb. 1, 2014. Published March 2014. Originallyapproved in 1971. Last previous edition approved in 2008 as C688 08. DOI:10.1520/C0688-14.2For refer
14、enced 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 Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced on
15、www.astm.org.*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 States1required to produce concrete of a given consistency and thataccelerates the setting or early strength develo
16、pment, 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 1This section is intended to
17、 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 Information4.1 The purchaser
18、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 contain notless than 9 percen
19、t 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 (C10/C10M, C150, C595, C845, and C1157) applicableto that type of cement. The method
20、shall be adequate for thequalitative and quantitative determination of the addition in thefinished cement, and shall be fully described in the report of thetests on the addition.”5.2 AggregatesThe aggregates used in the evaluation ofthe addition shall be in accordance with the Aggregates portionof t
21、he 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 Table 1 and Table 2
22、, except that if the test cementfails to meet the requirements of Table 1, but possesses all theTABLE 1 Criteria for Evaluating Neat Cement and Mortar Containing Functional Cement AdditionsTestsType of AdditionWater Reducing Retarding AcceleratingWater-Reducingand RetardingWater-Reducing andAccelera
23、tingSet-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:minIniti
24、alAt 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:
25、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 mo
26、ist 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 Shri
27、nkage 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 Vicat
28、 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 containin
29、g 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
30、cement.C688 142requirements 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 means for the quantitative determi-nation of the proposed addition in the finished cement, shall be
31、furnished 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 inwriting the cont
32、ent 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 testadditions are
33、 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 source and underthe
34、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 contain sufficien
35、t 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 the additions sh
36、allconform 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.TABLE 2 Criteria for Evaluating Concrete Containing Functional Cement AdditionsATestsType of AdditionWater Reducing Retarding AcceleratingWater-Reducingand Ret
37、ardingWater-Reducingand AcceleratingWater content, 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 e
38、arlier 3:30 later . 3:30 later .nor1:30 laterCompressive 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
39、90 1103 days 100 85 110 100 1107 days 100 90 100 100 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
40、 0.030 0.010 0.0103 months 0.010 0.010 0.030 0.010 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 requireme
41、nt for a retardingaddition is to require a level 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
42、at any previous testage. The objective of this 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 addit
43、ion may be approved after completion of the 3-monthstrength 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
44、 concrete.C688 1436.5 The amount of addition that is incorporated into thecement for evaluation purposes shall be such as to produce thedesired effects as listed in Table 1. When these tests showcompliance with the requirements of this specification, theaddition shall be used only in amounts up to t
45、he 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 with the functional
46、 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, mortar, or concrete
47、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, orlubricity, from t
48、hese 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, be deter-mined for
49、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 have metthe requirements
