ASTM_D_6108_-_13.pdf

Designation:D610813Standard Test Method forCompressive Properties of Plastic Lumber and Shapes1This standard is issued under the fixed designation D6108;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 This test method covers the determination of the me-chanical properties of plastic lumber and shapes,when theentire cross-section is loaded in compression at relatively lowuniform rates of straining or loading.Test specimens in the“as-manufactured”form are employed.As such,this is a testmethod for evaluating the properties of plastic lumber orshapes as a product and not a material property test method.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,or where the productis non-homogenous in the cross-section.1.3 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are forinformation 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 and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this test method.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to 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 SpecimensD6111 Test Method for Bulk Density And Specific Gravityof Plastic Lumber and Shapes by DisplacementE4 Practices for Force Verification of Testing MachinesE83 Practice for Verification and Classification of Exten-someter SystemsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 compressive deformationthe decrease in length pro-duced in the gage length of the test specimen by a compressiveload.It is expressed in units of length.3.1.2 compressive strainthe ratio of compressive defor-mation to the gage length of the test specimen,that is,thechange in length per unit of original gage length along thelongitudinal axis.It is expressed as a dimensionless ratio.3.1.3 compressive strengththe maximum compressivestress(nominal)carried by a test specimen during a compres-sion test.It may or may not be the compressive stress(nominal)carried by the specimen at the moment of rupture.3.1.4 compressive stress(nominal)the compressive loadper unit area of minimum(or effective as calculated inaccordance with Test Method D6111)original cross sectionwithin the gage boundaries,carried by the test specimen at anygiven moment.It is expressed in force per unit area.3.1.4.1 DiscussionThe expression of compressive stressin terms of the minimum original cross section is almostuniversally used.Under some circumstances the compressivestress has been expressed per unit of prevailing cross section.This stress is called the“true compressive stress”.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.20 on Plastic Lumber(SectionD20.20.01).Current edition approved June 1,2013.Published June 2013.Originallyapproved in 1997.Last previous edition approved in 2009 as D6108 09.DOI:10.1520/D6108-13.2For 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 States1 3.1.5 compressive stress-strain diagrama diagram inwhich values of compressive stress are plotted as ordinatesagainst corresponding values of compressive strain as abscis-sas.3.1.6 compressive yield pointthe first point on the stress-strain diagram at which an increase in strain occurs without anincrease in stress.3.1.7 modulus of elasticitythe ratio of compressive stress(nominal)to corresponding compressive strain below theproportional limit of a material.It is expressed in force per unitarea based on the effective/average initial cross-sectional area.3.1.8 percent compressive strainthe compressive defor-mation of a test specimen expressed as a percent of the originalgage length.3.1.9