ASTM_D_7522_-_D_7522M_-_21.pdf

Designation:D7522/D7522M21Standard Test Method forPull-Off Strength for FRP Laminate Systems Bonded toConcrete or Masonry Substrates1This standard is issued under the fixed designation D7522/D7522M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method describes the apparatus and procedurefor evaluating the pull-off strength of wet lay-up or pultruded(shop-fabricated)Fiber Reinforced Polymer(FRP)laminatesystems adhesively bonded to a flat concrete substrate.The testdetermines the greatest perpendicular force(in tension)that anFRP system can bear before a plug of material is detached.Failure will occur along the weakest plane within the systemcomprised of the test fixture,FRP laminate,adhesive,andsubstrate.1.2 This test method is primarily used for quality controland assessment of field repairs of structures using adhesive-applied composite materials.1.3 This test method is appropriate for use with FRPsystems having any fiber orientation or combination of plyorientations comprising the FRP laminate.1.4 This test method is appropriate for use with flatconcrete,concrete masonry,clay masonry,and stone masonrysubstrates.1.5 This test method is not appropriate for use as an“acceptance”or“proof”wherein the FRP system remainingintact at a prescribed force is an acceptable result.1.6 Pull-off strength measurements depend upon both ma-terial and instrumental parameters.Different adhesion testdevices and procedures will give different results and cannot bedirectly compared.1.7 This test method can be destructive.Spot repairs may benecessary.The test method will result in an exposed cut FRPsection;repair methods must consider the potential for mois-ture uptake through this cut section.1.8 Prior to the installation of some adhesively bonded FRPsystems,the substrate must be patched.This test method is notappropriate for determining the pull-off strength of the FRPfrom the patch material.An additional test method is requiredto determine the pull-off strength of the patch from thesubstrate.1.9 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system are not necessarily exact equiva-lents;therefore,to ensure conformance with the standard,eachsystem shall be used independently of the other,and valuesfrom the two systems shall not be combined.1.10 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.11 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established 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:2C125 Terminology Relating to Concrete and Concrete Ag-gregatesC1232 Terminology for MasonryD883 Terminology Relating to PlasticsD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsE6 Terminology Relating to Methods of Mechanical TestingE122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aLot or Process1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.10 onComposites for Civil Structures.Current edition approved Jan.1,2021.Published February 2021.Originallyapproved in 2009.Last previous edition approved in 2015 as D7522/D7522M 15.DOI:10.1520/D7522_D7522M-21.2For 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 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 issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.13.Terminology3.1 DefinitionsTerminology D3878 defines terms relatingto high-modulus fibers and their composites.TerminologyD883 defines terms relating to plastics.Terminology E6 definesterms relating to mechanical testing.Terminology C125 defin