1、Designation: D6662 13D6662 17Standard Specification forPolyolefin-Based Plastic Lumber Decking Boards1This standard is issued under the fixed designation D6662; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This specification covers polyolefin-based plastic lumber products for use as exterior residential decking boards.1.2 Pla
3、stic lumber products are currently made predominantly with recycled polyolefin plastics (in particular high-densitypolyethylene) where the products are more or less non-homogenous in the cross-section. However, this specification is alsopotentially applicable to similar manufactured plastic products
4、 made from other plastic and plastic composite materials that havenon-homogenous cross-sections.1.3 This specification details a procedure to calculate recommended span lengths for spacing of support joists. This procedurewas developed using experimental data from a typical unreinforced plastic lumb
5、er made predominantly from recycled high-densitypolyethylene. The methodology to develop span lengths for other types and compositions of plastic lumber is detailed in AppendixX1 of this standard.1.4 The values are stated in inch-pound units, as these are currently the most common units used by the
6、construction industry.Equivalent SI units are indicated in parentheses. However, the units stated for irradiance exposure in the weatherability section(6.3) are in SI units as these are the units commonly used for testing of this type.1.5 This standard does not purport to address all of the safety c
7、oncerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.NOTE 1There is no similar or equivalent ISO Standard.2. Referenced Documents2.1 Th
8、e following documents of the issue in effect on the date of material purchase form a part of this specification to the extentreferenced herein:2.2 ASTM Standards:2D883 Terminology Relating to PlasticsD2565 Practice for Xenon-Arc Exposure of Plastics Intended for Outdoor ApplicationsD2915 Practice fo
9、r Sampling and Data-Analysis for Structural Wood and Wood-Based ProductsD4329 Practice for Fluorescent Ultraviolet (UV) Lamp Apparatus Exposure of PlasticsD5033 Guide for Development of ASTM Standards Relating to Recycling and Use of Recycled Plastics (Withdrawn 2007)3D6109 Test Methods for Flexural
10、 Properties of Unreinforced and Reinforced Plastic Lumber and Related ProductsD6112 Test Methods for Compressive and Flexural Creep and Creep-Rupture of Plastic Lumber and ShapesD6341 Test Method for Determination of the Linear Coefficient of Thermal Expansion of Plastic Lumber and Plastic LumberSha
11、pes Between 30 and 140F (34.4 and 60C)E84 Test Method for Surface Burning Characteristics of Building MaterialsE108 Test Methods for Fire Tests of Roof CoveringsG151 Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light SourcesG154 Practice for Operating F
12、luorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Nonmetallic MaterialsG155 Practice for Operating Xenon Arc Light Apparatus for Exposure of Non-Metallic Materials1 This specification is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommitte
13、e D20.20 on Plastic Lumber.Current edition approved June 1, 2013March 1, 2017. Published June 2013March 2017. Originally approved in 2001. Last previous edition approved in 20092013 asD6662 - 09.D6662 - 13. DOI: 10.1520/D6662-13.10.1520/D6662-17.2 For referencedASTM standards, visit theASTM website,
14、 www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM
15、standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all
16、cases only the current versionof the standard as published by ASTM is to be considered the official document.*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 States13. Terminolo
17、gy3.1 Definitions:3.1.1 plastic lumber, na manufactured product made primarily from plastic materials (filled or unfilled), typically used as abuilding material for purposes similar to those of traditional lumber, which is usually rectangular in cross-section. (TerminologyD883)3.1.1.1 DiscussionPlas
18、tic lumber is typically supplied in sizes similar to those of traditional lumber board, timber and dimension lumber; howeverthe tolerances for plastic lumber and for traditional lumber are not necessarily the same. (Terminology D883)3.1.2 resin, na solid or pseudo solid organic material often of hig
19、h molecular weight, which exhibits a tendency to flow whensubjected to stress, usually has a softening or melting range, and usually fractures conchoidally. (Terminology D883)3.1.2.1 DiscussionIn a broad sense, the term is used to designate any polymer that is a basic material for plastics. (1982)3.
20、2 Definitions of Terms Specific to This Standard:3.2.1 bulgeconvex distortion (away from the center of the cross-section) of the face of the board from a straight line drawnfrom edge to edge across the width of the board.3.2.2 crookdistortion of the board in which there is a deviation in a direction
21、 perpendicular to the edge from a straight linefrom end to end of the board.3.2.3 cupconcave distortion (towards the center of the cross-section) of the face of the board from a straight line drawn fromedge to edge across the width of the board.3.2.4 edgethe side of a rectangular-shaped board corres
22、ponding to the thickness of the board.3.2.5 facethe side of a rectangular-shaped board corresponding to the width of the board.3.2.6 thicknessthe lesser dimension of the cross-sectional profile of a rectangular-shaped board.3.2.7 widththe greater dimension of the cross-sectional profile of a rectang
23、ular-shaped board.3.3 Additional definition of terms applying to this specification appear in Terminology D883 and D5033.4. Ordering Information4.1 The information contained in this specification is intended to be helpful to producers, distributors, regulatory agencies andusers. The information can
24、also promote understanding between purchasers and sellers. The purchaser shall state whether thisspecification is to be used, select the preferred options permitted herein, and include the allowable design information in theinvitation to bid and purchase order from the following:4.1.1 Title, number
25、and date of this specification,4.1.2 Minimum allowable bending strength and allowable bending stiffness,4.1.3 Percent recycled content (if requested),4.1.4 Flame spread index,4.1.5 Color,4.1.6 Quantity in lineal feet,4.1.7 Cut length,4.1.8 Cross-sectional dimensions,4.1.9 Packing requirements,4.1.10
26、 Palletization, if required,4.1.11 Marking, if other than specified.4.2 If specific mechanical property values are not required by the purchaser (for example, when purchasing materials for generalretail sales distribution and not for a specific project), the manufacturer shall provide minimum allowa
27、ble design information, aswould be determined under this specification, to aid in the application of the decking board material by the end user.D6662 1725. Dimensions and Permissible VariationsIt is permissible to produce decking boards either in sizes that are similar to the standard dimensions of
28、the wood industry, orto proprietary dimensions designed by manufacturers. This specification does not limit the dimensional range of production.For reference, the standards of the wood industry are as follows:5.1 ThicknessUnless otherwise specified in 4.1.8, boards shall be:Nominal (in.) Actual (in.
29、) Tolerance (in.)1 34 11654 1 1162 1-12 116Tolerance on thickness of boards thicker than 2 inches (nominal) shall be 6 116 inch.5.2 Width of BoardsUnless otherwise specified in paragraph 4.1.8, board widths shall be:Nominal (in.) Actual (in.) Tolerance (in.)3 2-12 1164 3-12 1166 5-12 1168 7-14 11610
30、 9-14 11612 11-14 116Tolerance on width of boards wider than 12 inches (nominal) shall be 6 116 inch.5.3 Length of Boardsunless otherwise specified in 4.1.7, boards up to 20 feet shall have tolerances of +12 inch or -116 inch.Over 20 feet, the tolerances will be +12-inch or -116 inch per 20-ft of le
31、ngth or fraction thereof. Measurement of lengths to be madeat 73 6 2 F and relative humidity of 50 6 5 %.5.4 Flatness ToleranceBoard shall be flat with maximum cup or bulge in the board face limited to the tolerances in Table 1.Linear interpolation of the values is acceptable for dimensions other th
32、an listed.5.5 SquarenessUnless a specially shaped member is specified, the cross-section of all boards shall be visually rectangular (thatis, the face and edge of the board are perpendicular to each other) and suited for the intended purpose.5.6 CrookCrook shall conform to the tolerances in Table 2.
33、 Linear interpolation of the values is acceptable for dimensionsother than listed.5.7 Tongue and GrooveBoards shall be without tongue and groove unless otherwise specified in 4.1.8. Because of loadtransfer between adjacent boards, the methodology and equations presented in section 6.1.4 for determin
34、ing recommendedmaximum span lengths are not applicable to tongue and groove boards. Manufacturers of tongue and groove decking boards shallprovide recommended span lengths based on sound engineering practice, taking into account some of the issues described in 6.1.4below, as well as previous, in-ser
35、vice performance history.6. Performance Requirements6.1 Flexural Properties:6.1.1 Test ProcedureD6109.6.1.2 Specimens TestedA minimum of 15 specimens shall be tested.6.1.3 Criteria(1) The mean value of the secant flexural modulus at 1 % outer fiber strain estimated statistically to within 5 %with 75
36、 % confidence shall equal or exceed 50 000 psi. Table 3 shows the number of specimens required to establish the meanvalue at 75 % confidence interval with 6 5 % error using Practice D2915. (2) The 5 % lower tolerance limit at 75 % confidenceflexural stress at 3 % outer fiber strain shall equal or ex
37、ceed 1000 psi. If any specimen fails prior to reaching 3 % strain, then theflexural strength at failure for that specimen shall equal or exceed 1000 psi. The 5 % lower tolerance limit at 75 % confidence iscomputed by subtracting K-times the standard deviation from the mean value, where K is tabulate
38、d in statistics handbooks (andin Table 3 of Practice D2915) as a factor for a one-sided tolerance limit for the distribution. Table 4 shows the value of K for severalsample sizes.NOTE 2Many standards require a minimum sample size of approximately 30 to balance testing costs against the large reducti
39、ons in the allowablevalues for very small sample sizes.NOTE 3A16 in. on center joist spacing is considered typical standard spacing for residential deck construction. While 50 000 psi is given as aminimum flexural modulus, a modulus greater than 50 000 psi is potentially required for some decking bo
40、ard sizes in order to meet this spacing whendetermining span lengths per the guidance presented in 6.1.4 below. Alternatively, use span lengths less than 16 in. on center as needed.NOTE 4Concurrent to the development of this specification for Plastic Lumber Decking, a Standard Guide for the Design a
41、nd Construction of PlasticTABLE 1 Cup or Bulge Tolerances Relative to Nominal Width ofthe Board FaceFace Width, in. #4 in. 6 in. 8 in. 10 in. 12 in.Tolerance 132 in. 116 in. 18 in. 316 in. 14 in.D6662 173Lumber Decking is being developed by Section D20.20.01 (under the Subcommittee D20.20 on Plastic
42、 Products). This Standard Guide is expected tobe available sometime after this Specification has been approved and in use.6.1.4 Span LengthsRecommended maximum span lengths shall be determined using the following equations:For concentrated loads on boards which are continuous over a minimum of two s
43、pans (such as decking boards) as shown in Fig.1, the maximum recommended span shall be limited by either the stress or the deflection formula as follow, whichever providesthe lesser span:Stress Formula:L 564S Fb!/13P! (1)Deflection Formula:L 567EI!/P k!#12 (2)For distributed (or uniform) loads on bo
44、ards which are continuous over a minimum of two spans (such as decking boards) asshown in Fig. 2, the maximum span shall be limited by either the stress or the deflection formula as follow, whichever providesthe lesser span:Stress Formula:L 58S Fb!144!/qb!#12 (3)Deflection Formula:L 5185EI!144!/qb k
45、!#13 (4)where:L = computed span length, in.,S = section modulus, in.3,Fb = allowable flexural stress as computed in 6.1.4.1, psi,P = concentrated load, lb,TABLE 2 Crook Tolerances Relative to Nominal Length and Widthof the BoardLength in Feet #4 in.Width6 in.Width8 in. Width 10 in.Width12 in.Width46
46、 38 in. 14 in. 316 in. 18 in. 18 in.8 12 in. 12 in. 38 in. 14 in. 316 in.10 34 in. 58 in. 12 in. 716 in. 38 in.12 1 in. 78 in. 1316 in. 34 in. 916 in.14 114 in. 118 in. 1 in. 78 in. 34 in.16 112 in. 138 in. 118 in. 1 in. 78 in.TABLE 3 Number of Specimens Required to Establish the MeanValue with an E
47、rror of 5 % with 75 % Confidence for VariousCoefficients of Variation (COV) in the Data SetCOV Range, % 1015 1520 2025 25No. of Specimens, N 15 23 34 60TABLE 4 Value of K for Establishing the Lower 5 % LowerTolerance Limit with 75 % Confidence for Various Sample SizesNo. of Specimens, N 15 30 Infini
48、teValue of K 1.991 1.869 1.645FIG. 1 Schematic of Concentrated Load on Boards that are Continuous Over Two SpansD6662 174E = effective modulus of elasticity as computed in 6.1.4.2, psi,I = moment of inertia, in.4 ,k = factor used to limit deflection to L/k (for example L/360 with k = 360; or L/120 w
49、ith k = 120),q = uniformly distributed load, lb/sq-ft,b = actual board width, in., and = Creep Adjustment Factor = 1.5.NOTE 5The attached commentary in Appendix X1 provides a rationale for the Creep Adjustment Factor, .6.1.4.1 Allowable Flexural StressThe allowable flexural stress, Fb, of the decking board is given as follows:Fb5Fb/FS!CDCT (5)where:Fb = the base flexural stress value for plastic lumber made of HDPE-type polyolefins for nor
