ASTM_C_642_-_13.pdf

Designation:C64213Standard Test Method forDensity,Absorption,and Voids in Hardened Concrete1This standard is issued under the fixed designation C642;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()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the determinations of density,percent absorption,and percent voids in hardened concrete.1.2 The text of this test method references notes andfootnotes which provide explanatory information.These notesand footnotes(excluding those in tables and figures)shall notbe considered as requirements of this standard.1.3 The values stated in SI units are to be regarded as thestandard.1.4 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.2.Significance and Use2.1 This test method is useful in developing the datarequired for conversions between mass and volume for con-crete.It can be used to determine conformance with specifica-tions for concrete and to show differences from place to placewithin a mass of concrete.3.Apparatus3.1 Balance,sensitive to 0.025%of the mass of thespecimen.3.2 Container,suitable for immersing the specimen andsuitable wire for suspending the specimen in water.4.Test Specimen4.1 Whenever possible,the sample shall consist of severalindividual portions of concrete,each to be tested separately.The individual portions may be pieces of cylinders,cores,orbeams of any desired shape or size,except that the volume ofeach portion shall be not less than 350 cm3(or for normalweight concrete,approximately 800 g);and each portion shallbe free from observable cracks,fissures,or shattered edges.5.Procedure5.1 Oven-Dry MassDetermine the mass of the portions,and dry in an oven at a temperature of 110 6 5C for not lessthan 24 h.After removing each specimen from the oven,allowit to cool in dry air(preferably in a desiccator)to a temperatureof 20 to 25C and determine the mass.If the specimen wascomparatively dry when its mass was first determined,and thesecond mass closely agrees with the first,consider it dry.If thespecimen was wet when its mass was first determined,place itin the oven for a second drying treatment of 24 h and againdetermine the mass.If the third value checks the second,consider the specimen dry.In case of any doubt,redry thespecimen for 24-h periods until check values of mass areobtained.If the difference between values obtained from twosuccessive values of mass exceeds 0.5%of the lesser value,return the specimens to the oven for an additional 24-h dryingperiod,and repeat the procedure until the difference betweenany two successive values is less than 0.5%of the lowest valueobtained.Designate this last value A.5.2 SaturatedMassAfterImmersionImmersethespecimen,after final drying,cooling,and determination ofmass,in water at approximately 21C for not less than 48 h anduntil two successive values of mass of the surface-dried sampleat intervals of 24 h show an increase in mass of less than 0.5%of the larger value.Surface-dry the specimen by removingsurface moisture with a towel,and determine the mass.Designate the final surface-dry mass after immersion B.5.3 Saturated Mass After BoilingPlace the specimen,processed as described in 5.2,in a suitable receptacle,coveredwith tap water,and boil for 5 h.Allow it to cool by natural lossof heat for not less than 14 h to a final temperature of 20 to25C.Remove the surface moisture with a towel and determinethe mass of the specimen.Designate the soaked,boiled,surface-dried mass C.5.4 Immersed Apparent MassSuspend the specimen,afterimmersion and boiling,by a wire and determine the apparentmass in water.Designate this apparent mass D.6.Calculation6.1 By using the values for mass determined in accordancewith the procedures described in Section 5,make the followingcalculations:1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.66 on Concretes Resistance to Fluid Penetration.Current edition approved Feb.1,2013.Published February 2013.Originallyapproved in 1969.Last previous edition approved in 2006 as C642 06.DOI:10.1520/C0642-13.*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 Absorption after immersion,%5B 2 A!/A#3100(1)Absorption after immersion and boiling,%5C 2 A!/A#3100(2)Bulk density,dry5A/C 2 D!#5 g1(3)Bulk density after immersion5B/C 2 D!#(4)Bulk density after immersion and boiling5C/C 2 D!#(5)Apparent density5A/A 2 D!#5 g2(6)Volume of permeable