1、Designation:C1646/C1646M16Standard Practice forMaking and Curing Test Specimens for EvaluatingResistance of Coarse Aggregate to Freezing and Thawing inAir-Entrained Concrete1This standard is issued under the fixed designation C1646/C1646M;the number immediately following the designation indicates th
2、eyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers procedures for making and curingtes
3、t specimens for evaluating resistance of normal-weightcoarse aggregates to freezing and thawing in air-entrainedconcrete in accordance with Test Method C666/C666M,Pro-cedure A or B.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated
4、 ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 This practice does not purport to address all the safetyconcerns,if any,associated with its use.It is the
5、responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.(WarningFresh hydraulic cementi-tious mixtures are caustic and may cause chemical burns toskin and tissue upon prolonged use.2)2.Refere
6、nced Documents2.1 ASTM Standards:3C33 Specification for Concrete AggregatesC39/C39M Test Method for Compressive Strength of Cylin-drical Concrete SpecimensC125 Terminology Relating to Concrete and Concrete Ag-gregatesC143/C143M Test Method for Slump of Hydraulic-CementConcreteC150 Specification for
7、Portland CementC173/C173M Test Method forAir Content of Freshly MixedConcrete by the Volumetric MethodC192/C192M Practice for Making and Curing Concrete TestSpecimens in the LaboratoryC231 Test Method for Air Content of Freshly Mixed Con-crete by the Pressure MethodC490 Practice for Use ofApparatus
8、for the Determination ofLength Change of Hardened Cement Paste,Mortar,andConcreteC494/C494M Specification for Chemical Admixtures forConcreteC666/C666M Test Method for Resistance of Concrete toRapid Freezing and ThawingD75 Practice for Sampling Aggregates2.2 ACI Standard:4211.1Practice for Selecting
9、 Proportions for Normal,Heavyweight,and Mass Concrete3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this specification,referto Terminology C125.4.Significance and Use4.1 This practice provides standard requirements for propor-tioning concrete,and for preparing and conditioning t
10、estspecimens suitable for evaluating the durability of coarseaggregate in air-entrained concrete subjected to freezing andthawing in accordance with Test Method C666/C666M.4.2 Concrete having an adequate air-void system may not beresistant to freezing and thawing if it contains coarse aggregatethat
11、becomes critically saturated.An aggregate particle isconsidered to be critically saturated when there is insufficientunfilled pore space to accommodate the expansion of water thataccompanies the freezing.1This practice is under the jurisdiction of ASTM Committee C09 on Concreteand ConcreteAggregates
12、 and is the direct responsibility of Subcommittee C09.67 onResistance to the Environment.Current edition approved June 1,2016.Published June 2016.Originallyapproved in 2007.Last previous edition approved in 2008 as C1646/C1646M 8a.DOI:10.1520/C1646_C1646M-16.2Section on Safety Precautions,Manual of
13、Aggregate and Concrete Testing,Annual Book of ASTM Standards,Volume 04.02.3For 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 Document Summary page onthe ASTM
14、website.4Available from American Concrete Institute(ACI),P.O.Box 9094,FarmingtonHills,MI 48333-9094,http:/www.aci-int.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 States1 5.A
15、pparatus5.1 Equipment for mixing concrete and procedures formaking and curing test specimens shall be in accordance withPractice C192/C192M.6.Coarse Aggregate Preparation6.1 SamplingSample in accordance with Practice D75.6.2 GradingWhen coarse aggregates are to be comparedusing this practice,standar
16、dize the coarse aggregate gradingsby recombining individual size fractions in accordance withTable 1 for the appropriate size aggregate being tested.Bringthe as-received sample to a saturated-surface-dry(SSD)con-dition or drier prior to sieving.Do not oven-dry the coarseaggregate sample.If necessary,air drying of the sample toachieve this condition is permitted.The nominal-maximum-aggregate size shall not exceed one-third the least dimension ofthe test specimen to be used.Fine aggregate shall me
