1、Designation:C845/C845M18Standard Specification forExpansive Hydraulic Cement1This standard is issued under the fixed designation C845/C845M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parenth
2、eses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers hydraulic cements that expandduring the early hardening period after setting.1.2 The values stated in either SI units or inch-pou
3、nd unitsare to be regarded separately as standard.The values stated 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 The text of this standard references no
4、tes and footnoteswhich provide explanatory material.These notes and footnotes(excluding those in tables and figures)shall not be consideredas requirements of this standard.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization esta
5、blished in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2C33/C33M Specification for Concrete AggregatesC109/C109M Test Meth
6、od for Compressive Strength ofHydraulic Cement Mortars(Using 2-in.or 50-mm CubeSpecimens)C114 Test Methods for Chemical Analysis of HydraulicCementC183/C183M Practice for Sampling and the Amount ofTesting of Hydraulic CementC185 Test Method for Air Content of Hydraulic CementMortarC188 Test Method f
7、or Density of Hydraulic CementC465 Specification for Processing Additions for Use in theManufacture of Hydraulic CementsC688 Specification for Functional Additions for Use inHydraulic CementsC806 Test Method for Restrained Expansion of ExpansiveCement MortarC807 Test Method for Time of Setting of Hy
8、draulic CementMortar by Modified Vicat Needle3.Terminology3.1 Definitions:3.1.1 expansive cement(K)an expansive cement contain-ing anhydrous calcium aluminosulfate(4CaO3Al2O3SO3),calcium sulfate,and uncombined calcium oxide.3.1.2 expansive cement(M)an expansive cement contain-ing calcium aluminate c
9、ement and calcium sulfate.3.1.3 expansive cement(S)an expansive cement contain-ing tricalcium aluminate(C3A)and calcium sulfate.3.1.4 expansive hydraulic cementa cement composed es-sentially of hydraulic calcium silicates,calcium aluminates andcalcium sulfates,which,upon being mixed with water,forms
10、 apaste that increases significantly in volume during the earlyhardening period occurring after setting.This volume increaseis due principally to the reaction of the calcium aluminates andcalcium sulfates.3.1.5 shrinkage-compensating concreteconcrete that is in-ternally restrained with resilient rei
11、nforcing and made withexpansive cement which induces both compressive stress in theconcrete and positive steel strain that approximately off-setstensile stresses and negative strains induced by drying shrink-age.4.Classification4.1 The cement covered by this specification is suitable foruse in shrin
12、kage-compensating concrete and shall be desig-nated as Type E-1.NOTE1Three kinds of expansive cement are identified in Section 3 bythe letters K,M,and S.The appropriate letter should be used as a suffixto the type designation when one of these kinds is desired.Expansivecement may also be prepared in
13、 other ways.1This specification is under the jurisdiction of ASTM Committee C01 onCement and is the direct responsibility of Subcommittee C01.13 on SpecialCements.Current edition approved July 1,2018.Published July 2018.Originally approvedin 1976.Last previous edition approved in 2012 as C845 12.DOI
14、:10.1520/C0845_C0845M-18.2For 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.Copyright ASTM International,100 Barr Har
15、bor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations
16、issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 5.Ordering Information5.1 When it is desired that an optional requirement apply orthat the cement be of a particular kind,a specific request to thiseffect should be made by the purchaser.6.Chemical Composition6.1 Expansive cement shall conform to the requirements asto chemical composition prescribed in Table 1.6.2 The purchaser has the option of specifying that thealkalies(Na2O+0.658K2O)shall not exceed 0.60%(seeT
