ASTM_C_682_-_94.pdf

Designation:C 682 94Standard Practice forEvaluation of Frost Resistance of Coarse Aggregates in Air-Entrained Concrete by Critical Dilation Procedures1This standard is issued under the fixed designation C 682;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 practice covers the evaluation of frost resistance ofcoarse aggregates in air-entrained concrete.It was developedparticularly for use with normal weight aggregates not havingvesicular,highly porous structure.1.2 The values stated in inch-pound units are to be regardedas the standard.2.Referenced Documents2.1 ASTM Standards:C 33 Specification for Concrete Aggregates2C 138 Test Method for Unit Weight,Yield,and Air Content(Gravimetric)of Concrete2C 143 Test Method for Slump of Hydraulic Cement Con-crete2C 150 Specification for Portland Cement2C 171 Specification for Sheet Materials for Curing Con-crete2C 173 Test Method for Air Content of Freshly MixedConcrete by the Volumetric Method2C 192 Practice for Making and Curing Concrete Test Speci-mens in the Laboratory2C 231 Test Method for Air Content of Freshly MixedConcrete by the Pressure Method2C 260 Specification forAir-EntrainingAdmixtures for Con-crete2C 295 Guide for Petrographic Examination of Aggregatesfor Concrete2C 671 Test Method for Critical Dilation of Concrete Speci-mens Subjected to Freezing2E 104 Practice for Maintaining Constant Relative Humidityby Means of Aqueous Solutions32.2ACI Standard:211.1 Standard Practice for Selecting Proportions for Nor-mal,Heavyweight,and Mass Concrete43.Significance and Use3.1 This practice is primarily intended to provide the pro-spective user with a technique for estimating the frost suscep-tibility of concrete aggregates for known or assumed fieldenvironmental conditions.The significance of the results interms of potential field performance will depend upon thedegree to which field conditions can be expected to correlatewith those employed in the laboratory.It is of utmost impor-tance,therefore,that the user of this practice assess at first thefollowing anticipated field exposure conditions:3.1.1 The condition of the aggregate as it enters the concretemixture(that is,stream wet,partially saturated,or dry),3.1.2 The curing procedures anticipated for the concrete,3.1.3 The age and degree of saturation of the concrete whenfirst exposed to freezing,3.1.4 The length of the season of potential exposure tofreezing temperatures,the frequency of freezing and thawingcycles,and the minimum temperature to be reached by theconcrete,at the given location,3.1.5 The accessibility of water to the concrete during theperiod of potential frost damage,and3.1.6 Effect of climatic conditions between seasons offreezing weather on the degree of saturation of the concrete atthe onset of freezing.3.2 The laboratory moisture conditioning procedures speci-fied in 5.3 and 7.4 are intended to permit simulation of a rangeof environments that aggregates and concretes might beexpected to encounter under field conditions.This approachprovides information by which to estimate durability whenthere is a lack of knowledge as to actual field conditions.4.Apparatus4.1 The apparatus shall be in accordance with Test MethodC 671.5.Coarse Aggregate Preparation5.1 SamplingSample in accordance with the applicablesections of Guide C 295.5.2 GradingWhen aggregates are to be compared usingthis practice,gradings of each must be within the limits setforth in Table 1 of Specification C 33.The nominal maximum1This practice is under the jurisdiction of ASTM Committee C-9 on Concreteand Concrete Aggregatesand is the direct responsibility of Subcommittee C09.67onResistance of Concrete to Its Environment.Current edition approved March 15,1994.Published May 1994.Originallypublished as C 682 71 T.Last previous edition C 682 87(1992)e1.2Annual Book of ASTM Standards,Vol 04.02.3Annual Book of ASTM Standards,Vol 11.03.4Manual of Concrete Practice,Am.Concrete Institute,Part I,1985.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superceded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.aggregate size shall not exceed one third the minimum dimen-sion of the test specimen to be used.5.3 ConditioningWhenever possible,maintain the aggre-gates to be tested in or bring to the condition representative ofthat which might be expected in the field.It should be noted,however,that aggregate moisture states other than dry orsaturated are very difficult to maintain during preparation oftests specimens.Reproducibility of over-all test results is likelyto be affected adversely by variability in aggregate moisture.NOTE1If the aggregates are not proc