ASTM D7031-2011 4375 Standard Guide for Evaluating Mechanical and Physical Properties of Wood-Plastic Composite Products《木塑复合材料产品物理力学性能评价指导》.pdf

1、Designation: D7031 11Standard Guide forEvaluating Mechanical and Physical Properties of Wood-Plastic Composite Products1This standard is issued under the fixed designation D7031; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the

2、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. Scope1.1 This guide covers test methods appropriate for evaluat-ing a wide range of performance properties for wood-pla

3、sticcomposite (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 particula

4、r 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 stand

5、ard 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:2C1308 Test Method for Accelerated Leach Test for Diffu-sive Releases from Solidified Waste and a ComputerProgram to Model Diffu

6、sive, Fractional Leaching fromCylindrical Waste FormsD9 Terminology Relating to Wood and Wood-Based Prod-uctsD143 Test Methods for Small Clear Specimens of TimberD792 Test Methods for Density and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD883 Terminology Relating to PlasticsD10

7、37 Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel MaterialsD1038 Terminology Relating to Veneer and PlywoodD1413 Test Method for Wood Preservatives by LaboratorySoil-Block CulturesD1554 Terminology Relating to Wood-Base Fiber and Par-ticle Panel MaterialsD1761 Test Meth

8、ods for Mechanical Fasteners in WoodD1929 Test Method for Determining Ignition Temperatureof PlasticsD2017 Test Method of Accelerated Laboratory Test ofNatural Decay Resistance of WoodsD2047 Test Method for Static Coefficient of Friction ofPolish-Coated Flooring Surfaces as Measured by theJames Mach

9、ineD2394 Test Methods for Simulated Service Testing ofWood and Wood-Base Finish FlooringD2395 Test Methods for Specific Gravity of Wood andWood-Based MaterialsD2481 Test Method for Accelerated Evaluation of WoodPreservatives for Marine Services by Means of Small SizeSpecimensD2565 Practice for Xenon

10、-Arc Exposure of Plastics In-tended for Outdoor ApplicationsD2915 Practice for Sampling and Data-Analysis for Struc-tural Wood and Wood-Based ProductsD3345 Test Method for Laboratory Evaluation of Wood andOther Cellulosic Materials for Resistance to TermitesD4000 Classification System for Specifying

11、 Plastic Materi-alsD4060 Test Method for Abrasion Resistance of OrganicCoatings by the Taber AbraserD4092 Terminology for Plastics: Dynamic MechanicalPropertiesD4442 Test Methods for Direct Moisture Content Measure-ment of Wood and Wood-Base MaterialsD4495 Test Method for Impact Resistance of Poly(V

12、inylChloride) (PVC) Rigid Profiles by Means of a FallingWeightD4761 Test Methods for Mechanical Properties of Lumberand Wood-Base Structural MaterialD5379/D5379M Test Method for Shear Properties of Com-posite Materials by the V-Notched Beam MethodD5456 Specification for Evaluation of Structural Comp

13、ositeLumber Products1This 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 May 1, 2011. Published June 2011. Originallyapproved in 2004. Last previous edition approved i

14、n 2004 as D703104. DOI:10.1520/D7031-11.2For 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.1Copyright ASTM Inter

15、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D5764 Test Method for Evaluating Dowel-Bearing Strengthof Wood and Wood-Based ProductsD6109 Test Methods for Flexural Properties of Unrein-forced and Reinforced Plastic Lumber and Related Prod-uctsD6341 Tes

16、t Method for Determination of the Linear Coef-ficient ofThermal Expansion of Plastic Lumber and PlasticLumber Shapes Between 30 and 140F (34.4 and 60C)D6662 Specification for Polyolefin-Based Plastic LumberDecking BoardsE84 Test Method for Surface Burning Characteristics ofBuilding MaterialsE108 Tes

17、t Methods for Fire Tests of Roof CoveringsE661 Test Method for Performance of Wood and Wood-Based Floor and Roof Sheathing Under ConcentratedStatic and Impact LoadsE1354 Test Method for Heat and Visible Smoke ReleaseRates for Materials and Products Using an Oxygen Con-sumption CalorimeterF1679 Test

18、Method for Using a Variable Incidence Tribom-eter (VIT)3G154 Practice for Operating Fluorescent Light Apparatusfor UV Exposure of Nonmetallic Materials2.2 AWPA Standards:4AWPA Standard E1 Standard Method for LaboratoryEvaluation for Determination of Resistance to Subterra-nean TermitesAWPA Standard

19、E7 Standard Method for Evaluating WoodPreservatives by Field Tests with StakesAWPA Standard E10 Standard Method of Testing WoodPreservatives by Laboratory Soil-Block Cultures3. Terminology3.1 DefinitionsTerminology used to describe WPCs isdefined in Terminology D9, D883, D1038, D1554, D4092, andClas

20、sification D4000.3.2 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 thetypes used to make the products.3.2.2 thicknessthe lesser d

21、imension 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.3.2.5 wood-plastic composite (WPC)a composite madeprimarily from

22、 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 described withinare intended to address products that are manuf

23、actured 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 Mechanical and Physical Properties5.1 The following mechanical a

24、nd 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 applications will not require assessment oftension or compression p

25、roperties.5.2 SamplingSamples for testing shall be representativeof the population being evaluated. Sampling shall be conductedin accordance with applicable portions of Practice D2915 andbe representative of the possible variations due to changes inraw materials and process variables over time. It i

26、s 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 property to be estimated, the actual variation in the propertyoc

27、curring in the population, and the precision with which theproperty is to be estimated. The principles of Practice D2915shall be followed.NOTE 1If code listed allowable design values or performance ratingsare the objective, it is recommended that all sampling and testing beconducted or witnessed, or

28、 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 importantconsiderations, the test specimens shall be conditioned

29、 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 within 30 minupon removal from the treatment.3Withdrawn. The last

30、approved version of this historical standard is referencedon www.astm.org.4Available from American Wood-Preservers Association (AWPA), P.O. Box388, Selma, AL 36702-0388, http:/.L direction - Parallel to the longitudinal direction of the member (length)X direction - Parallel to the wide surface of th

31、e member and normal to the Ldirection (width)Y direction - Normal to both the L and X direction (thickness)FIG. 1 Orientation for Wood-Plastic CompositesD7031 1125.5 BendingModulus of rupture (MOR) or moment capac-ity and apparent modulus of elasticity (E) or flexural stiffnessshall be determined in

32、 accordance with principles of TestMethods D4761 or D6109. 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 dimensio

33、ns establishes the unit volumefor analysis of volume effects in accordance with SpecificationD5456, 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 configur

34、ation shall be recorded (see X1.5). 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 exce

35、ptionally large deformations prior 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

36、specimen. If the calculation is 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 re

37、ported for each specimen. Charac-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 st

38、ress shall be used.NOTE 4To assign 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-plast

39、ic products.5.6 Tension Parallel to the L DirectionTension strengthparallel to the L direction shall be evaluated by testing inaccordance with the principles of Test Methods D4761. Speci-men cross section shall not be less than the minimum antici-pated structural size. Specimen length between grips

40、shall be aminimum of 12 times the 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 anal

41、ysis ofvolume effects per Specification D5456.5.7 Compression Parallel to the L DirectionShort columncompression strength parallel to the L direction shall bedetermined in accordance with the principles of Test MethodsD4761. Tests shall be conducted on a cross section no less thanthe minimum anticip

42、ated structural size. Length of 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 Compress

43、ion Perpendicular to the L DirectionCompression strength perpendicular to the L direction shall bedetermined following the measurement and bearing require-ments of Test Method D143, except that the specimen dimen-sions shall be the full cross-section dimension of the WPC, andthe length shall be thre

44、e times the depth. Load shall be 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 fo

45、r general product application. 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 S

46、hear)Shear strength parallel to the L direction shall be determinedin accordance with the principles of Test Method D143 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)

47、in the sheararea is acceptable 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

48、 to the L DirectionShearstrength perpendicular to the L direction shall be determined inaccordance with the principles of Test Method D143 using theshear block test. The Test Method D143 shear block test hasbeen shown to provide a conservative estimate of the shearstrength of wood-based materials. O

49、ther test methods may beapplicable. 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 testperpendicular 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 D5379/D5379M,will provide additional