ASTM_C_1723_-_16.pdf

Designation:C172316Standard Guide forExamination of Hardened Concrete Using Scanning ElectronMicroscopy1This standard is issued under the fixed designation C1723;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.Scope1.1 This guide provides information for the examination ofhardened concrete using scanning electron microscopy(SEM)combined with energy-dispersive X-ray spectroscopy(EDX orEDS).Since the 1960s,SEM has been used for the examinationof concrete and has proved to be an insightful tool for themicrostructural analysis of concrete and its components.Thereare no standardized procedures for the SEM analysis ofconcrete.SEM supplements techniques of light microscopy,which are described in Practice C856,and,when applicable,techniques described in Practice C856 should be consulted forSEM analysis.For further study,see the bibliography at the endof this guide.1.2 This guide is intended to provide a general introductionto the application of SEM/EDS analytical techniques for theexamination and analysis of concrete.It is meant to be usefulto engineers and scientists who want to study concrete and whoare familiar with,but not expert in,the operation and applica-tion of SEM/EDS technology.The guide is not intended toprovide explicit instructions concerning the operation of thistechnology or interpretation of information obtained throughSEM/EDS.1.3 It is critical that petrographer or operator or both befamiliar with the SEM/EDX(EDS)equipment,specimenpreparation procedures,and the use of other appropriateprocedures for this purpose.This guide does not discuss datainterpretation.Proper data interpretation is best done byindividuals knowledgeable about the significance and limita-tions of SEM/EDX(EDS)and the materials being evaluated.1.4 The SEM provides images that can range in scale froma low magnification(for example,15)to a high magnification(for example,50 000 or greater)of concrete specimens suchas fragments,polished surfaces,or powders.These images canprovide information indicating compositional or topographicalvariations in the observed specimen.The EDX(EDS)systemcan be used to qualitatively or quantitatively determine theelemental composition of very small volumes intersecting thesurface of the observed specimen(for example,1-10 cubicmicrons)and those measured compositional determinationscan be correlated with specific features observed in the SEMimage.See Note 1.NOTE1An electronic document consisting of electron micrographsand EDX(EDS)spectra illustrating the materials,reaction products,andphenomena discussed below is available at http:/netfiles.uiuc.edu/dlange/www/CML/index.html.1.5 Performance of SEM and EDX(EDS)analyses onhardened concrete specimens can,in some cases,presentunique challenges not normally encountered with other mate-rials analyzed using the same techniques.1.6 This guide can be used to assist a concrete petrographerin performing or interpreting SEM and EDX(EDS)analyses ina manner that maximizes the usefulness of these techniques inconducting petrographic examinations of concrete and othercementitious materials,such as mortar and stucco.For a morein-depth,comprehensive tutorial on scanning electron micros-copy or the petrographic examination of concrete and concrete-related materials,the reader is directed to the additionalpublications referenced in the bibliography section of thisguide.1.7 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.1.8 This standard does not purport to address all of thesafety concerns,if any,associated with the use of electronmicroscopes,X-ray spectrometers,chemicals,and equipmentused to prepare samples for electron microscopy.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.Referenced Documents2.1 ASTM Standards:21This guide is under the jurisdiction of ASTM Committee C09 on Concrete andConcrete Aggregates and is the direct responsibility of Subcommittee C09.65 onPetrography.Current edition approved Sept.1,2016.Published October 2016.Originallyapproved in 2010.Last previous edition approved in 2010 as C1723 10.DOI:10.1520/C1723-16.2For 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 Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 C125 Terminology Relating to Concrete and Concrete Ag-gregatesC294 Descriptive Nomenclature for Constituents of Con-crete AggregatesC295 Guide for Petrogra