1、Designation: D 5456 08Standard Specification forEvaluation of Structural Composite Lumber Products1This standard is issued under the fixed designation D 5456; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONStructural composite lumber is intended for use as an engineering material for a variety of end-useapplications. The composition o
3、f the lumber varies by wood species, adhesive composition, woodelement size, shape, and arrangement. To provide the intended performance, composite lumberproducts require: (1) an evaluation of the mechanical and physical properties and their response toend-use environments, and (2) establishment of
4、and conformance to standard performance specifica-tions for quality.Procedures contained in this specification are also to be used for establishing the design propertiesand for checking the effectiveness of property assignment and quality assurance procedures.The quality assurance sections in this s
5、pecification are intended to serve as a basis for designingquality-control programs specific to each product. The objective is to ensure that design valuesestablished in the qualification process are maintained.This specification is arranged as follows:SectionQualification 6Determination of Allowabl
6、e Design Stresses 7Independent Inspection 8Quality Assurance 101. Scope1.1 This specification recognizes the complexity of struc-tural glued products. Consequently, this specification coversboth specific procedures and statements of intent that samplingand analysis must relate to the specific produc
7、t.1.2 This specification was developed in the light of cur-rently manufactured products as defined in 3.2. Materials thatdo not conform to the definitions are beyond the scope of thisspecification. A brief discussion is found in Appendix X1.1.3 Details of manufacturing procedures are beyond thescope
8、 of this specification.NOTE 1There is some potential for manufacturing variables to affectthe properties of members that are loaded for sustained periods of time.Users of this specification are advised to consider the commentary on thistopic in Appendix X1.1.4 This specification primarily considers
9、end use in dryservice conditions, such as with most protected framing mem-bers, where the average equilibrium moisture content forsolid-sawn lumber is less than 16 %. The conditioning envi-ronment of 6.3 is considered representative of such uses.1.5 The performance of structural composite lumber isa
10、ffected by wood species, wood element size and shape, andadhesive and production parameters. Therefore, products pro-duced by each individual manufacturer shall be evaluated todetermine their product properties, regardless of the similarityin characteristics to products produced by other manufacture
11、rs.Where a manufacturer produces product in more than onefacility, each production facility shall be evaluated indepen-dently. For additional production facilities, any revisions to thefull qualification program in accordance with this specificationshall be approved by the independent qualifying age
12、ncy.1.6 This specification is intended to provide manufacturers,regulatory agencies, and end users with a means to evaluate acomposite lumber product intended for use as a structuralmaterial.1.7 This specification covers initial qualification sampling,mechanical and physical tests, analysis, and des
13、ign valueassignments. Requirements for a quality-control program andcumulative evaluations are included to ensure maintenance ofallowable design values for the product.1This specification is under the jurisdiction of ASTM Committee D07 on Woodand is the direct responsibility of Subcommittee D07.02 o
14、n Lumber and EngineeredWood Products.Current edition approved Nov. 1, 2008. Published December 2008. Originallyapproved in 1993. Last previous edition approved in 2007 as D 5456 07.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1.8
15、This specification, or parts thereof, shall be applicable tostructural composite lumber portions of manufactured struc-tural components.1.9 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided f
16、or information onlyand are not considered standard.1.10 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
17、 regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded-Hot-Plate ApparatusC 355 Test Methods for Water Vapor Transmission of ThickMaterials3C 384 Test Method
18、 for Impedance and Absorption ofAcoustical Materials by Impedance Tube MethodC 423 Test Method for Sound Absorption and Sound Ab-sorption Coefficients by the Reverberation Room MethodD9 Terminology Relating to Wood and Wood-Based Prod-uctsD 143 Test Methods for Small Clear Specimens of TimberD 150 T
19、est Methods for AC Loss Characteristics and Per-mittivity (Dielectric Constant) of Solid Electrical Insula-tionD 198 Test Methods of Static Tests of Lumber in StructuralSizesD 245 Practice for Establishing Structural Grades and Re-lated Allowable Properties for Visually Graded LumberD 669 Test Metho
20、d for Dissipation Factor and PermittivityParallel with Laminations of Laminated Sheet and PlateMaterialsD 1037 Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel MaterialsD 1666 Test Methods for Conducting Machining Tests ofWood and Wood-Base MaterialsD 1761 Test Methods fo
21、r Mechanical Fasteners in WoodD 2132 Test Method for Dust-and-Fog Tracking and Ero-sion Resistance of Electrical Insulating MaterialsD 2394 Test Methods for Simulated Service Testing ofWood and Wood-Base Finish FlooringD 2395 Test Methods for Specific Gravity of Wood andWood-Based MaterialsD 2559 Sp
22、ecification for Adhesives for Structural Lami-nated Wood Products for Use Under Exterior (Wet Use)Exposure ConditionsD 2718 Test Methods for Structural Panels in Planar Shear(Rolling Shear)D 2915 Practice for Evaluating Allowable Properties forGrades of Structural LumberD 3201 Test Method for Hygros
23、copic Properties of Fire-Retardant Wood and Wood-Based ProductsD 3755 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating MaterialsUnder Direct-Voltage StressD 4442 Test Methods for Direct Moisture Content Measure-ment of Wood and Wood-Base MaterialsD 4
24、761 Test Methods for Mechanical Properties of Lumberand Wood-Base Structural MaterialD 4933 Guide for Moisture Conditioning of Wood andWood-Based MaterialsD 5055 Specification for Establishing and MonitoringStructural Capacities of Prefabricated Wood I-JoistsD 5457 Specification for Computing Refere
25、nce Resistanceof Wood-Based Materials and Structural Connections forLoad and Resistance Factor DesignD 5764 Test Method for Evaluating Dowel-BearingStrength of Wood and Wood-Based ProductsD 6815 Specification for Evaluation of Duration of Loadand Creep Effects of Wood and Wood-Based ProductsE84 Test
26、 Method for Surface Burning Characteristics ofBuilding MaterialsE119 Test Methods for Fire Tests of Building Constructionand Materials2.2 CSA Standards:4CSA Standards for Wood Adhesives O112-M Series3. Terminology3.1 DefinitionsStandard definitions of wood terms aregiven in Terminology D9.3.2 Defini
27、tions of Terms Specific to This Standard:3.2.1 Exposure 1 durabilitya bond classification forwood-based products that are not permanently exposed to theweather. Wood-based products classified as Exposure 1 areintended to resist the effects of moisture on structural perfor-mance due to construction d
28、elays or other conditions of similarseverity.3.2.2 structural composite lumberin this specification,structural composite lumber (SCL) is any of laminated veneerlumber (LVL), parallel strand lumber (PSL), laminated strandlumber (LSL), or oriented strand lumber (OSL). These mate-rials are intended for
29、 structural use and they shall be bondedwith an exterior adhesive.3.2.2.1 laminated strand lumbera composite of woodstrand elements with wood fibers primarily oriented along thelength of the member. The least dimension of the strands shallnot exceed 0.10 in. (2.54 mm) and the average length shall be
30、a minimum of 150 times the least dimension.3.2.2.2 laminated veneer lumbera composite of woodveneer sheet elements with wood fibers primarily oriented2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand
31、ards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from Canadian Standards Association (CSA), 5060 Spectrum Way,Mississauga, ON L4W 5N6, Canada, http:/www.c
32、sa.ca.D5456082along the length of the member. Veneer thickness shall notexceed 0.25 in. (6.4 mm).3.2.2.3 oriented strand lumbera composite of woodstrand elements with wood fibers primarily oriented along thelength of the member. The least dimension of the strands shallnot exceed 0.10 in. (2.54 mm) a
33、nd the average length shall bea minimum of 75 times the least dimension.3.2.2.4 parallel strand lumbera composite of wood ve-neer strand elements with wood fibers primarily oriented alongthe length of the member. The least dimension of strands shallnot exceed 0.25 in. (6.4 mm) and the average length
34、 shall be aminimum of 300 times the least dimension.3.2.3 DiscussionSCL has three mutually perpendiculardirections of orientation (see Fig. 1):L DirectionParallel to the longitudinal direction of the member.X DirectionParallel to a surface of the member and normal to the L direction.Y DirectionNorma
35、l to both L and X direction.In this specification, longitudinal shear means shear stress inthe L-X and L-Y planes. Planar shear is stress in the X-Y plane.4. Materials4.1 Wood ElementsWood elements used in the fabricationof SCL products shall conform to 3.2.4.2 AdhesivesAdhesives used in the fabrica
36、tion of SCLproducts shall conform to the requirements in SpecificationD 2559. Alternatively, the durability of high temperature cur-ing adhesives can be evaluated with the procedures specified inAnnex A4.2 (see Note 2). For this procedure, the averagestrength retention shall be at least 50 %. In Can
37、ada, adhesivesshall conform to the appropriate section of CSA O112-MSeries, CSA Standards for Wood Adhesives.NOTE 2Adhesives evaluated by Annex A4.2 are only qualified forExposure 1 conditions; other conditions are beyond the scope of thisspecification. See the commentary and the section on Design a
38、ndMechanical Property Concerns in Appendix X1 for further information.5. Mechanical Properties5.1 The characteristic value for SCL is a statistic derivedfrom test data as specified in 7.1. For bending and tensionparallel to grain, the characteristic value is obtained at the unitvolume as specified i
39、n 6.5.1 and 6.5.2.5.2 The design stress related to SCL is derived from thecharacteristic value through application of the adjustmentslisted in Table 1 of this specification.5.3 The allowable design stress published for engineeringuse shall be derived from the design stress modified by factorsgiven i
40、n 7.3.6. Qualification6.1 Samples for qualification testing shall be representativeof the population being evaluated. When an intentional modi-fication to the process results in a reduction in mechanicalproperties as indicated by the quality-control program, thennew qualification is required.6.1.1 Q
41、ualification tests shall be conducted or witnessed bya qualified agency in accordance with 8.1.All test results are tobe certified by the qualified agency.6.2 Sampling of the test material shall be done in accor-dance with applicable portions of Section 3, Statistical Meth-odology, of Practice D 291
42、5.6.2.1 Design stress, except for compression perpendicular tograin and apparent modulus of elasticity, shall be based on thefifth percentile tolerance limit.6.2.2 The confidence level for calculating tolerance limitsand confidence intervals shall be 75 %.6.2.3 Minimum sample size for calculating to
43、lerance limitson fifth percentiles shall be 53. When volume effect tests aremade at multiple sizes for bending and tension, the minimumsample shall be 78 specimens at the unit volume specimen size.6.2.3.1 The calculated fifth percentile parametric tolerancelimits (PTL) shall have a standard error no
44、 greater than 5 % ofthe PTL, when evaluated in accordance with 3.4.3.2 of PracticeD 2915. When necessary the sample shall be increased beyondthe minimum of 53, to meet this requirement.6.2.4 Minimum unit sample sizes for compression perpen-dicular to grain (see 6.5.4) shall provide estimation of mea
45、nvalues within 5 % in accordance with 3.4.2 of Practice D 2915.Minimum sample size shall not be less than 30.6.3 Composite lumber used in qualification testing shall bebrought to moisture equilibrium in a conditioned environmentof 20 6 6C (68 6 11F) and 65 % (65 %) relative humidity.Methods for dete
46、rmination of completion of conditioning aregiven in Guide D 4933.6.4 Moisture content and specific gravity shall be measuredand reported for each specimen tested in the qualificationFIG. 1 Orientations for Structural Composite LumberTABLE 1 Adjustment FactorsNOTE 1Apparent modulus of elasticity is c
47、omputed from a deforma-tion, and compression strength perpendicular to grain is established at adeformation limit. Neither is subject to load duration adjustments. Allother factors are the product of 1.62, that adjusts data to normal durationas defined in 7.3.1 of Practice D 245, and an additional f
48、actor foruncertainty (see Appendix X3 for an explanation of the shear block testadjustment factor).Property Adjustment FactorApparent modulus of elasticity 1.00Bending strength 2.10Tensile strength parallel to grain 2.10Compressive strength parallel to grain 1.90Longitudinal shear strengthShear bloc
49、k test 3.15Structural-size shear test 2.10Compressive strength perpendicular to grain 1.67D5456083program. Measurement for moisture content shall be in accor-dance with Test Methods D 4442 and measurement of specificgravity shall be in accordance with Test Methods D 2395.6.5 Mechanical PropertiesThe properties that shall beevaluated by qualification testing shall include, but are notlimited to: bending strength and stiffness, tensile strengthparallel to the grain, compressive strength parallel to the grain,compressive strength perpendicular to the grain, and long
