1、Designation:D 6435 99Standard Test Method forShear Properties of Plastic Lumber and Plastic LumberShapes1This standard is issued under the fixed designation D 6435;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revi
2、sion.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the me-chanical properties of plastic lumber and plastic lumber shapeswhen loaded in s
3、hear at relatively low uniform rates ofstraining or loading.1.2 Plastic lumber and plastic lumber shapes are currentlymade predominately with recycled plastics where the productis nonhomogenous in the cross section.However,this testmethod would also be applicable to similarly manufacturedplastic pro
4、ducts made from virgin resins or where the productis nonhomogenous in the cross section.1.3 The values stated in inch-pound units are to be regardedas the standard.The SI units given in parentheses are forinformation only.1.4 This standard does not purport to address all of thesafety concerns,if any
5、,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 similar or equivalent ISO standard.2.Referenced Documents2.1 ASTM Standards:D 6
6、18 Practice for Conditioning Plastics and ElectricalInsulating Materials for Testing2D 883 Terminology Relating to Plastics2D 2915 Practice for Evaluating Allowable Properties forGrades of Structural Lumber3D 4000 Classification System for Specifying Plastic Mate-rials4D 5033 Guide for the Developme
7、nt of Standards Relating tothe Proper Use of Recycled Plastics5E 4 Practices for Force Verification of Testing Machines63.Terminology3.1 Definitions:3.1.1 plastic lumber,na manufactured product composedof more than 50 weight percent resin,and in which the productgenerally is rectangular in cross sec
8、tion and typically suppliedin sizes that correspond to traditional lumber board anddimension lumber sizes,that may be filled or unfilled,and thatmay be composed of single or multiple resin blends.3.1.2 plastic lumber shape,na plastic lumber,whichgenerally is not rectangular in cross section.3.1.3 re
9、sin,na solid or pseudosolid organic material oftenof high molecular weight,which exhibits a tendency to flowwhen subjected to stress,usually has a softening or meltingrange,and usually fractures conchoidally(see TerminologyD 883).3.1.3.1 DiscussionIn a broad sense,the term is used todesignate any po
10、lymer that is a basic material for plastics.3.1.4 shear stress(nominal)the shear force per unit areaof the shear surface of the test specimen.It is expressed inforce per unit area.3.2 Additional definitions of terms applying to this testmethod appear in Terminology D 883 and Guide D 5033.4.Significa
11、nce and Use4.1 Shear tests provide information about the shear proper-ties of plastic lumber when employed under conditions ap-proximating those under which the tests are made.For manymaterials,there may be a specification that requires the use ofthis test method,but with some procedural-modificatio
12、ns thattake precedence when adhering to the specification.Therefore,it is advisable to refer to that material specification before usingthis test method.Table 1 in Classification D 4000 lists theASTM materials standards that currently exist.4.2 Shear properties are limited to shear strength only.In
13、thecase of a material that fails in shear by a fracture,the shearstrength has a very definite value.In the case of a material that1This test method is under the jurisdiction ofASTM Committee D-20 on Plasticsand is the direct responsibility of Subcommittee D20.20 on Plastic Products.Current edition a
14、pproved June 10,1999.Published September 1999.2Annual Book of ASTM Standards,Vol 08.01.3Annual Book of ASTM Standards,Vol 04.10.4Annual Book of ASTM Standards,Vol 08.02.5Annual Book of ASTM Standards,Vol 08.03.6Annual Book of ASTM Standards,Vol 03.01.1Copyright ASTM International,100 Barr Harbor Dri
15、ve,PO Box C700,West Conshohocken,PA 19428-2959,United States.does not fail in shear by a fracture,the shear strength is basedon the maximum load carried by the test specimen.Manyplastic lumber materials may not fail in the classic shear mode;that is,separation of the test specimen into two pieces by
16、failure along the critical shear surface.4.3 Shear tests provide a standard method of obtaining datafor research and development,design,quality control,accep-tance,or rejection under specifications.The tests cannot beconsidered appropriate for engineering design in applicationsdiffering widely from the load-time scale of the standard test.Such applications may require additional tests,such as impact,creep,and fatigue.5.Apparatus5.1 Testing MachineAny suitable testing machine capableof satisfacto
