ASTM_D_7337_-_D_7337M_-_12.pdf

Designation:D7337/D7337M12Standard Test Method forTensile Creep Rupture of Fiber Reinforced Polymer MatrixComposite Bars1This standard is issued under the fixed designation D7337/D7337M;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 outlines requirements for tensile creeprupture testing of fiber reinforced polymer matrix(FRP)composite bars commonly used as tensile elements inreinforced,prestressed,or post-tensioned concrete.1.2 Data obtained from this test method are used in designof FRP reinforcements under sustained loading.The procedurefor calculating the one-million hour creep-rupture capacity isprovided in Annex A1.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.Within the text,theinch-pound units are shown in brackets.The values stated ineach system are not exact equivalents;therefore,each systemmust be used independently of the other.Combining valuesfrom the two systems may result in nonconformance with thestandard.1.4 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.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsD7205/D7205M Test Method for Tensile Properties of FiberReinforced Polymer Matrix Composite BarsE4 Practices for Force Verification of Testing MachinesE456 Terminology Relating to Quality and StatisticsE1012 Practice for Verification of Testing Frame and Speci-men Alignment Under Tensile and Compressive AxialForce Application3.Terminology3.1 Terminology in D3878 defines terms relating to high-modulus fibers and their composites.Terminology in D883defines terms relating to plastics.Terminology in E6 definesterms relating to mechanical testing.Terminology in E456defines terms relating to statistics and the selection of samplesizes.In the event of a conflict between terms,Terminology inD3878 shall have precedence over the other terminologystandards.3.2 Definitions of Terms Specific to This Standard:3.2.1 anchor,na protective device placed on each end ofa bar,between the bar and the grips of the tensile testingapparatus,to prevent grip-induced damage.Usually used onbars with irregular surfaces,as opposed to flat strips wherebonded tabs are more typical.3.2.2 anchoring section,nthe end parts of the specimenwhere an anchor is fitted to transmit the forces from the testingapparatus to the test section.3.2.3 bar,na linear element,often with surface undula-tions or a coating of particles that promote mechanical inter-lock with concrete.3.2.4 creep,ntime-dependent deformation(or strain)un-der sustained force(or stress).3.2.5 creep rupture,nmaterial failure caused by sustainedforce(or stress)over time.3.2.6 creep rupture capacity,nthe force at which failureoccurs after a specified period of time from initiation of asustained force.The predicted force causing failure at 1 millionhours is referred to as the million-hour creep rupture capacity.This capacity is determined by the method described in theAnnex.3.2.7 creep rupture strength,nthe stress causing failureafter a specified period of time from initiation of a sustainedforce.3.2.8 creep rupture time,nthe lapsed time between thestart of a sustained force and failure of the test specimen.1This 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 Sept.1,2012.Published December 2012.Originallyapproved in 2007.Last previous edition approved in 2007 as D7337/D7337M 07.DOI:10.1520/D7337_D7337M-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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.9 failure,nrupture of the bar under test into twoseparate pieces.3.2.10 force ratio,nthe ratio of a constant sustained forceapplied to a specimen to its tensile capacity as determinedaccording to Test Method D7205/D7205M.3.2.11 grid,na two-dimensional(planar)or three-dimensional(spatial)rigid array of interconnected FRP barsthat form a contiguous lattice that can be used to reinforceconcrete.The lattice can be manufactured with integrallyconne