ASTM_C_156_-_11.pdf

Designation:C15611Standard Test Method forWater Loss from a Mortar Specimen Through LiquidMembrane-Forming Curing Compounds for Concrete1This standard is issued under the fixed designation C156;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.This standard has been approved for use by agencies of the Department of Defense.1.Scope*1.1 This test method covers laboratory determination of theefficiency of liquid membrane-forming compounds for curingconcrete,as measured by their ability to reduce moisture lossfrom mortar specimens during the early hardening period.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.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.(WarningFreshhydraulic cementitious mixtures are caustic and may causechemical burns to skin and tissue upon prolonged exposure.)22.Referenced Documents2.1 ASTM Standards:3C87 Test Method for Effect of Organic Impurities in FineAggregate on Strength of MortarC150 Specification for Portland CementC230/C230M Specification for Flow Table for Use in Testsof Hydraulic CementC305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC778 Specification for SandD1475 Test Method For Density of Liquid Coatings,Inks,and Related ProductsD1653 Test Methods for Water Vapor Transmission of Or-ganic Coating FilmsD2369 Test Method for Volatile Content of CoatingsE178 Practice for Dealing With Outlying Observations3.Significance and Use3.1 The moisture retaining ability of a product as deter-mined by this test method is used to assess the suitability ofmaterials for contributing to an appropriate curing environmentfor concrete.The laboratory test method is used both informulating and in specifying or qualifying curing products.This test method gives the user a measure of the ability oftested curing materials to impede the escape of moisture froma hydraulic cement mortar.Since it is desirable to retainmoisture in fresh concrete to promote the hydration process,failure of the product to minimize the escape of moisture maylead to loss of strength,cracking,shrinkage,or low abrasionresistance of the hardened concrete,or a combination thereof.3.2 Many factors affect the laboratory test results.Testresults obtained may be highly variable as indicated by theprecision statement.Critical factors include the precision of thecontrol of the temperature,humidity and air circulation in thecuring cabinet,preparation and sealing of the mortarspecimens,the age and surface condition of the mortar speci-men when the curing product is applied,and the uniformity andquantity of application of the curing membrane.4.Apparatus4.1 Mechanical Mortar Mixer,as described in PracticeC305,or a larger size mixture operating on the same principle.4.2 Flow Table,as described in Specification C230/C230M.4.3 Molds shall be made of metal,glass,hard rubber,orplastic,and shall be watertight and rigidly constructed toprevent distortion during molding of the specimens or handlingof the mold containing fresh mortar.They shall have aminimum surface area of 12000 mm2(18.6 in.2),and aminimum depth of 19 mm(34in.).The top surface shall beround,square,or rectangular with length not more than twicethe width.The top of the mold shall have a rim to provide afirm level surface to support the wood float and to facilitate the1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.22 on Materials Applied to New Concrete Surfaces.Current edition approved June 1,2011.Published June 2011.Originallyapproved in 1940.Last previous edition approved in 2009 as C15609a.DOI:10.1520/C0156-11.2Section on Safety Precautions,Manual of Aggregate and Concrete Testing,Annual Book of ASTM Standards,Vol 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 website.*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 grooving and sealing steps of the procedure.The rim shall beparallel with the bottom surface of the mold.NOTE1Take care to avoid use of an excessive amount of oil,grease,or mol