ASTM_C_684_-_99_2003.pdf

Designation:C 684 99(Reapproved 2003)Standard Test Method forMaking,Accelerated Curing,and Testing ConcreteCompression Test Specimens1This standard is issued under the fixed designation C 684;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers four procedures for making,curing,and testing specimens of concrete stored under condi-tions intended to accelerate the development of strength.Thefour procedures are:Procedure AWarm Water Method,ProcedureBBoilingWaterMethod,ProcedureCAutogenous Curing Method,and Procedure DHighTemperature and Pressure Method.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are provided forinformation purposes only.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is 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.See Section 9 andNote 9 and Note 14 for specific warnings and precautions.2.Referenced Documents2.1 ASTM Standards:2C 31/C 31M Practice for Making and Curing Concrete TestSpecimens in the FieldC 39 Test Method for Compressive Strength of CylindricalConcrete SpecimensC 172 Practice for Sampling Freshly Mixed ConcreteC 177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded-Hot-Plate ApparatusC 192/C 192M Practice for Making and Curing ConcreteTest Specimens in the LaboratoryC 470 Specification for Molds for Forming Concrete TestCylinders VerticallyC 617 Practice for Capping Cylindrical Concrete Speci-mensC 1231 Practice for Use of Unbonded Caps in Determina-tion of Compressive Strength of Hardened Concrete Cyl-indersD 3665 Practice for Random Sampling of ConstructionMaterialsE 105 Practice for Probability Sampling of MaterialsE 122 Practice for Calculating Sample Size to Estimate,With a Specified Tolerable Error,the Average for Charac-teristics of a Lot or ProcessE 141 Practice for Acceptance of Evidence Based on theResults of Probability Sampling3.Terminology3.1 There are no terms in this standard that require new orother than dictionary definitions.4.Summary of Test Method4.1 Concrete specimens are exposed to accelerated curingconditions that permit the specimens to develop a significantportion of their ultimate strength within a time period rangingfrom 5 to 49 h,depending upon the procedure that is used.Procedures A and B utilize storage of specimens in heatedwater at elevated curing temperatures without moisture loss.The primary function of the moderately heated water used inProcedure A is to serve as insulation to conserve the heatgenerated by hydration.The temperature level employed inProcedure B provides thermal acceleration.Procedure C in-volves storage of specimens in insulated curing containers inwhich the elevated curing temperature is obtained from heat ofhydration of the cement.The sealed containers also preventmoisture loss.Procedure D involves simultaneous applicationof elevated temperature and pressure to the concrete usingspecial containers.Sampling and testing procedures are thesame as for normally cured specimens(see Practice C 172 andTest Method C 39,respectively).1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.61 on Testing for Strength.Current edition approved Nov.10,1999.Published February 2000.Originallyapproved in 1971.Last previous edition approved in 1999 as C 684 99.2For 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 website.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.4.2 Important characteristics of these procedures are shownin Table 1.5.Significance and Use5.1 The accelerated curing procedures provide,at the earli-est practical time,an indication of the potential strength of aspecific concrete mixture.These procedures also provideinformation on the variability of the production process for usein quality control.5.2 The accelerated early strength obtained from any of theprocedures in this test method can be used to evaluate concretestrengths in the same way conventional 28-day strengths havebeen used in the past,with suitable changes in the expectedstrength values.Since the practice of using strength valuesobtained from standard-cured cylinders at 28 days is longestablished and widespread,the results of accelerated strengthtests are often used to estimate