ASTM_C_418_-_12.pdf

Designation:C41812Standard Test Method forAbrasion Resistance of Concrete by Sandblasting1This standard is issued under the fixed designation C418;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 U.S.Department of Defense.1.Scope*1.1 This test method covers determination of the abrasionresistance characteristics of concrete by subjecting it to theimpingement of air-driven silica sand.It is intended for use asa basis for the development of informed judgment.1.2 The values stated in SI units are to be regarded as thestandard.Inch-pound units are shown for information purposesin parentheses.1.3 The text of this standard references notes and footnoteswhich are provided as explanatory material.These notes andfootnotes(excluding those in tables and figures)shall not beconsidered as requirements of this standard.1.4 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.NOTE1Users of this test method are advised that there are knownsafety hazards associated with the use of silica as a blasting media.Consult the silica manufactures MSDS to insure that the latest recom-mended health and safety practices are being followed.NOTE2Other procedures are available for measuring abrasion resis-tance of concrete surfaces in addition to subjecting it to air driven silicasand.Consideration should be given to other methods of testing asoutlined in ASTM C779/C779M,ASTM C944,and ASTM C1138.Thetest method most closely representing service conditions should be used.2.Referenced Documents2.1 ASTM Standards:2C125 Terminology Relating to Concrete and Concrete Ag-gregatesC127 Test Method for Relative Density(Specific Gravity)and Absorption of Coarse AggregateC778 Specification for SandC779/C779M Test Method for Abrasion Resistance of Hori-zontal Concrete SurfacesC944 Test Method for Abrasion Resistance of Concrete orMortar Surfaces by the Rotating-Cutter MethodC1138 Test Method for Abrasion Resistance of Concrete(Underwater Method)3.Terminology3.1 For definitions of terms used in this standard,refer toTerminology C125.4.Significance and Use4.1 This test method covers the laboratory evaluation of therelative resistance of concrete surfaces to abrasion.Thisprocedure simulates the action of waterborne abrasives andabrasives under traffic on concrete surfaces.It performs acutting action that tends to abrade more severely the lessresistant components of the concrete.5.Apparatus5.1 ScalesThe scale shall have a capacity of 5000 g ormore.The permissible variation at a load of 5000 g(11 lb)shallbe 6 0.5 g(0.2 oz).5.2 WeightsThe permissible variations on weights used inweighing shall be as prescribed in Table 1.The permissiblevariations on new weights shall be one half of the values givenin Table 1.5.3 Sand Blast ApparatusThe sand blast apparatus shallconsist of an injector-type gun.The gun shall have a high-velocity air jet fed by a suitably controlled rate of flow for theabrasive material.The nozzle shown in Fig.1 shall consist ofcold-rolled bar stock,40 mm(1.5 in.)long,or hardened toolsteel HRC 48 6 2 as determined by Test Methods E18,drilledto 6.40 6 0.02 mm(0.250 6 0.001 in.)approximately 700 kPa(100 psi)through the center.The walls of the nozzle shall havea 45 bevel on the inside at the upper end.A compressed airsupply of approximately 100 psi(690 kPa)shall be availableand equipped with a pressure-control device.Provision shall bemade to collect the spent abrasive and dust.Suitable jigs andclamps shall be provided to hold the test specimen in a fixedposition with relation to the discharge end of the nozzle.For1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.62 on Abrasion Testing.Current edition approved Dec.1,2012.Published January 2013.Originallyapproved in 1958.Last previous edition approved in 2005 as C418 05.DOI:10.1520/C0418-12.2For 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.*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 laboratory wear testing of concrete specimens a commercialsand blast cabinet may be selected similar to that shown in Fig.2.5.4 ShieldThe shield shall be square or circular,150 mm(6 in.)on a side or di