ASTM_D_6112_-_18.pdf

Designation:D611218Standard Test Methods forCompressive and Flexural Creep and Creep-Rupture ofPlastic Lumber and Shapes1This standard is issued under the fixed designation D6112;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.Scope*1.1 These test methods cover the determination of the creepand creep-rupture properties of plastic lumber and shapes,when loaded in compression or flexure under specified envi-ronmental conditions.Test specimens in the“as-manufactured”form are employed.As such,these are test methods forevaluating the properties of plastic lumber or shapes as aproduct and not material property test methods.1.2 Plastic lumber and plastic shapes are currently madepredominantly with recycled plastics.However,this testmethod would also be applicable to similar manufacturedplastic products made from virgin resins where the product isnon-homogenous in the cross-section.1.3 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are for informa-tion only.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this standard.1.5 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:2D543 Practices for Evaluating the Resistance of Plastics toChemical ReagentsD883 Terminology Relating to PlasticsD2990 Test Methods for Tensile,Compressive,and FlexuralCreep and Creep-Rupture of PlasticsD4000 Classification System for Specifying Plastic Materi-alsD5033 Guide for Development ofASTM Standards Relatingto Recycling and Use of Recycled Plastics(Withdrawn2007)3D5947 Test Methods for Physical Dimensions of SolidPlastics SpecimensE4 Practices for Force Verification of Testing Machines3.Terminology3.1 Definitions:3.1.1 compressionin a compressive creep test,the de-crease in length produced in the gauge length or the total lengthof a test specimen.3.1.2 creep modulusthe ratio of initial applied stress tocreep strain.3.1.3 creep strainthe total strain,at any given time,produced by the applied stress during a creep test.3.1.3.1 DiscussionThe term creep,as used in this testmethod,reflects current plastics engineering usage.In scientificpractice,creep is often defined to be the nonelastic portion ofstrain.However,this definition is not applicable to existingengineering formulas.Plastics have a wide spectrum of retar-dation times,and elastic portions of strain cannot be separatedin practice from nonelastic.Therefore,wherever“strain”ismentioned in these test methods,it refers to the sum of elasticstrain plus the additional strain with time.3.1.4 deflectionin a flexural creep test,the change inmid-span position of a test specimen.3.1.5 deformationa change in shape,size or position of atest specimen as a result of compression,deflection,or exten-sion:1These test methods are under the jurisdiction of ASTM Committee D20 onPlastics and are the direct responsibility of Subcommittee D20.20 on Plastic Lumber(Section D20.20.01).Current edition approved June 1,2018.Published June 2018.Originallyapproved in 1997.Last previous edition approved in 2013 as D6112-13.DOI:10.1520/D6112-18.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.*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 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.1 3.1.6 plastic lumber,na manufactured product made pri-marily from plastic materials(filled or unfilled),typically usedas a building material for purposes similar to those of tradi-tional lumber,which is usually rectangular in cross-section.(Terminology D883)3.1.6.1 DiscussionPlastic lumber is typically suppli