1、Designation: D 7031 04Standard Guide forEvaluating Mechanical and Physical Properties of Wood-Plastic Composite Products1This standard is issued under the fixed designation D 7031; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e year of last revision. 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 guide covers test methods appropriate for evaluat-ing a wide range of performance properties for wood-
3、plasticcomposite (WPC) products. It was developed from evaluationsof both experimental and currently manufactured products, andis not intended to suggest that all the tests listed are necessaryor appropriate for each application of a WPC. The user mustdetermine which test methods apply to the partic
4、ular applica-tion being evaluated (see Appendix X1).1.2 Details of manufacturing processes may be proprietaryand are beyond the scope of this guide.1.3 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 st
5、andard 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:2C 1308 Test Method for Accelerated Leach Test for Diffu-sive Releases from Solidified Waste and a ComputerProgram to Model D
6、iffusive, Fractional Leaching fromCylindrical Waste FormsD 9 Terminology Relating to WoodD 143 Test Methods for Small Clear Specimens of TimberD 696 Test Method for Coefficient of Linear Thermal Ex-pansion of Plastics Between 30C and 30C with aVitreous Silica DilatometerD 792 Test Methods for Densit
7、y and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD 883 Terminology Relating to PlasticsD 1037 Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel MaterialsD 1038 Terminology Relating to Veneer and PlywoodD 1413 Test Method for Wood Preservatives by Labor
8、atorySoil-Block CulturesD 1554 Terminology Relating to Wood-Base Fiber andParticle Panel MaterialsD 1761 Test Methods for Mechanical Fasteners in WoodD 1929 Test Method for Determining Ignition Temperatureof PlasticsD 2017 Test Method for Accelerated Laboratory Test ofNatural Decay Resistance of Woo
9、ds3D 2047 Test Method for Static Coefficient of Friction ofPolish-Coated Flooring Surfaces as Measured by theJames MachineD 2394 Methods for Simulated Service Testing of Woodand Wood-Base Finish FlooringD 2395 Test Methods for Specific Gravity of Wood andWood-Based MaterialsD 2481 Test Method for Ac
10、celerated Evaluation of WoodPreservatives for Marine Services by Means of Small SizeSpecimensD 2565 Practice for Xenon Arc Exposure of Plastics In-tended for Outdoor ApplicationsD 2915 Practice for Evaluating Allowable Properties forGrades of Structural LumberD 3345 Test Method for Laboratory Evalua
11、tion of Woodand Other Cellulosic Materials for Resistance to TermitesD 4000 Classification System for Specifying Plastic Mate-rialsD 4060 Test Method for Abrasion Resistance of OrganicCoatings by the Taber AbraserD 4092 Terminology: Plastics: Dynamic Mechanical Prop-ertiesD 4442 Test Methods for Dir
12、ect Moisture Content Measure-ment of Wood and Wood-Base MaterialsD 4495 Test Method for Impact Resistance of Poly(VinylChloride) (PVC) Rigid Profiles by Means of a FallingWeightD 4761 Test Methods for Mechanical Properties of Lumberand Wood-Base Structural MaterialD 5379 Test Method for Shear Proper
13、ties of Composite1This guide is under the jurisdiction of ASTM Committee D07 on Wood and isthe direct responsibility of Subcommittee D07.02 on Lumber and Engineered WoodProducts.Current edition approved Oct. 1, 2004. Published October 2004.2For referenced ASTM standards, visit the ASTM website, www.
14、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.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United St
15、ates.Materials by the V-Notched Beam MethodD 5456 Specification for Evaluation of Structural Compos-ite Lumber ProductsD 5764 Test Method for Evaluating Dowel-BearingStrength of Wood and Wood-Base ProductsD 6109 Test Methods for Flexural Properties of Unrein-forced and Reinforced Plastic LumberD 666
16、2 Specification for Polyolefin-Based Plastic LumberDecking BoardsE 84 Test Method for Surface Burning Characteristics ofBuilding MaterialsE 108 Test Methods for Fire Tests of Roof CoveringsE 661 Test Method for Performance of Wood and Wood-Based Floor and Roof Sheathing Under ConcentratedStatic and
17、Impact LoadsE 1354 Test Method for Heat and Visible Smoke ReleaseRates for Materials and Products Using an Oxygen Con-sumption CalorimeterF 1679 Test Method for Using a Variable Incidence Tribom-eter (VIT)G 154 Practice for Operating Fluorescent Light Apparatusfor UV Exposure of Nonmetallic Material
18、s2.2 AWPA Standards:4AWPA Standard E1 Standard Method for LaboratoryEvaluation for Determination of Resistance to Subterra-nean TermitesAWPA Standard E7 Standard Method for Evaluating WoodPreservatives by Field Tests with Stakes3. Terminology3.1 DefinitionsTerminology used to describe WPCs isdefined
19、 in Terminology D 9, D 883, D 1038, D 1554, D 4092,and Classification D 4000.3.2 Definitions of Terms Specific to this Standard:3.2.1 recycled productsproducts composed of post-consumer material or recovered material, or both, that may ormay not have been subject to additional processing steps of th
20、etypes used to make the products.3.2.2 thicknessthe lesser dimension perpendicular to thelong axis.3.2.3 virgin material a material that has not been sub-jected to use or processing other than that required for its initialmanufacture3.2.4 widththe greater dimension perpendicular to thelong axis.3.2.
21、5 wood-plastic composite (WPC)a composite madeprimarily from wood- or cellulose-based materials and plas-tic(s).3.3 OrientationWPCs have three principal directions (seeFig. 1).4. Significance and Use4.1 WPCs are intended for use in both structural andnon-structural applications. The test methods des
22、cribed withinare intended to address products that are manufactured fromvirgin or recycled wood and thermoplastic sources. Thesemethods provide a reference for the evaluation of severalmechanical and physical properties important for structural andnon-structural uses of WPCs.5. Determination of Mech
23、anical and Physical Properties5.1 The following mechanical and physical properties areincluded to provide a complete set of reference tests for a broadrange of users. Some applications of WPCs will not requireassessment of all properties. For example, products that will belimited to flexural applica
24、tions will not require assessment oftension or compression properties.5.2 SamplingSamples for testing shall be representativeof the population being evaluated. Sampling shall be conductedin accordance with applicable portions of Practice D 2915 andbe representative of the possible variations due to
25、changes inraw materials and process variables over time. It is essential toconsider batch-to-batch and shift-to-shift variability whensampling actual production. Test specimens shall be selectedfrom several production runs of a given item.5.3 Sample SizeSelection of a sample size depends uponthe pro
26、perty to be estimated, the actual variation in the propertyoccurring in the population, and the precision with which theproperty is to be estimated. The principles of Practice D 2915shall be followed.NOTE 1If code listed allowable design values or performance ratingsare the objective, it is recommen
27、ded that all sampling and testing beconducted or witnessed, or both, by a qualified inspection agency.5.4 ConditioningPrior to testing, all specimens shall beconditioned to environmental conditions appropriate for theintended end use of the product.5.4.1 When temperature and relative humidity are im
28、portantconsiderations, the test specimens shall be conditioned for aperiod of time such that the average daily mass change of thetest specimen is less than 2 % of the mass at time of measure.5.4.2 When the product is to be subjected to a water soakenvironment, the test specimens shall be tested with
29、in 30 minupon removal from the treatment.5.5 BendingModulus of rupture (MOR) or moment capac-ity and apparent modulus of elasticity (E) or flexural stiffnessshall be determined in accordance with principles of Test4Available from American Wood-Preservers Association (AWPA), P.O. Box388, Selma, AL 36
30、702-0388, http:/.L direction - Parallel to the longitudinal direction of the member (length)X direction - Parallel to the wide surface of the member and normal to the Ldirection (width)Y direction - Normal to both the L and X direction (thickness)FIG. 1 Orientation for Wood-Plastic CompositesD703104
31、2Methods D 4761 or D 6109. For some applications and prod-ucts, moment capacity and flexural stiffness are preferableperformance measures. Whenever possible, the test specimenshall be the full cross section of the as-manufactured product.Selection of specimen dimensions establishes the unit volumefo
32、r analysis of volume effects in accordance with SpecificationD 5456, when applicable. A span-to-depth ratio of not less than16 shall be used. The specimens shall be loaded at a constantstrain rate of 1 % per minute (610 %). Average time to failurefor each test configuration shall be recorded (see X1
33、.5). Aconstant strain rate of 1 % per minute is achieved by using aconstant rate of test machine cross-head motion, R, (inches/minute) computed in terms of the test span, L, and the memberdepth, d, by the following equation:R 5 0.00185 3L2dNOTE 2WPCs often exhibit exceptionally large deformations pr
34、ior tofailure in bending. Users are cautioned to take particular care in testmachine set-up to accommodate large deflections, both in terms ofdeflection measuring devices and support conditions.5.5.1 MORMaximum load for the calculation of MORshall be reported for each specimen. If the calculation is
35、 basedon a load other than the maximum load, the load basis shall bereported.NOTE 3For products that exhibit large deformations, the MOR valueis commonly based on the load at 3 % strain.5.5.2 EApparent flexural modulus of elasticity and itscalculation basis shall be reported for each specimen. Chara
36、c-terization of the modulus of elasticity depends upon the use ofthe data. For material property information, E can be calculatedin a variety of ways. For design value assignment purposeslinear least squares fit of the stress-strain curve over anappropriate range of stress shall be used.NOTE 4To ass
37、ign design values to structural members the leastsquares fit over a range of 10 to 40 % of ultimate stress is commonlychosen as representative for service loadings. An alternative calculationmethod based on the secant modulus to 1 % strain is commonly used forall-plastic products.5.6 Tension Paralle
38、l to the L DirectionTension strengthparallel to the L direction shall be evaluated by testing inaccordance with the principles of Test Methods D 4761.Specimen cross section shall not be less than the minimumanticipated structural size. Specimen length between grips shallbe a minimum of 12 times the
39、actual test specimen width. Thespecimens shall be loaded at a constant strain rate of 1 % perminute (610 %). Average time to failure for each test configu-ration shall be recorded. If required, selection of specimendimensions establishes the unit volume for the analysis ofvolume effects per Specific
40、ation D 5456.5.7 Compression Parallel to the L directionShort columncompression strength parallel to the L direction shall bedetermined in accordance with the principles of Test MethodsD 4761. Tests shall be conducted on a cross section no less thanthe minimum anticipated structural size. Length of
41、the speci-men shall be such that l/d is less than 4.5 and greater than 3.0,where l is the effective unsupported length and d is theminimum cross-sectional dimension. For non-solid cross-section materials, the actual cross-sectional area shall becalculated.5.8 Compression Perpendicular to the L direc
42、tionCompression strength perpendicular to the L direction shall bedetermined following the measurement and bearing require-ments of Test Method D 143, except that the specimen dimen-sions shall be the full cross-section dimension of the WPC, andthe length shall be three times the depth. Load shall b
43、e appliedthrough a metal bearing plate across the full width of the testspecimen. Stress at both 0.02 and 0.04 in. (0.5 and 1.0 mm) ofdeformation shall be reported. Testing shall be conducted withstresses applied normal to the L-X or L-Y plane, or both, whenrequired for general product application.
44、The objective of thistest is to determine the load carrying capacity of the as-manufactured product. The allowable stress derived from thistest will only apply to the actual cross section tested.5.9 Shear Strength:5.9.1 Shear Parallel to the L direction (longitudinal shear)Shear strength parallel to
45、 the L direction shall be determinedin accordance with the principles of Test Method D 143 usingthe shear block test. Testing shall be done to produce shearfailure in the L-X or L-Y plane, or both. For solid cross-sectionproducts, a minimum dimension of 1.0 in. (25 mm) in the sheararea is acceptable
46、 provided that the total shear area is at least1.0 in2. For non-solid cross-section products, the full crosssection shall be tested using the shear block tests with theactual shear area based on wall thickness(s) subjected to theshearing stress.5.9.2 Shear Perpendicular to the L directionShearstreng
47、th perpendicular to the L direction shall be determined inaccordance with the principles of Test Method D 143 using theshear block test. The Test Method D 143 shear block test hasbeen shown to provide a conservative estimate of the shearstrength of wood-based materials. Other test methods may beappl
48、icable. Testing shall be done to produce shear failure in theX-Y plane. For solid cross-section products a minimum dimen-sion of 1.0 in. (25 mm) in the shear area is acceptable providedthat the total shear area is at least 1.0 in2.NOTE 5For non-solid cross-section products, a shear block testperpend
49、icular to the L direction may not be practical. For some specialcases, such as nonhomogeneous materials or non-solid cross-sectionproducts, alternative test methods such as Test Method D 5379, willprovide additional insight into actual shear strength material properties.5.10 Creep-Recovery and Creep-Rupture:NOTE 6When building code listed design values are the objective ofthe investigation, consideration of creep-recovery and creep-rupture aregenerally required.5.10.1 Creep-RecoveryA minimum of ten specimens rep-resentative of the population bei
