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TM_D_4761_
_13
Designation:D476113Standard Test Methods forMechanical Properties of Lumber and Wood-Base StructuralMaterial1This standard is issued under the fixed designation D4761;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the 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.INTRODUCTIONNumerous evaluations of the mechanical properties of wood-based structural material have beensatisfactorily conducted since the late 1920s,using Test Methods D198.Those methods are best suitedto a laboratory environment and are adaptable to a variety of products such as stress-graded lumber,sawn timber,laminated timbers,wood-plywood composite members,reinforced and prestressedtimbers.The procedures presented in these test methods have been derived from those set forth in TestMethods D198.They are intended primarily for application to stress-graded lumber,but can be usedfor other wood-base structural material as well.The procedures are more flexible than those in TestMethods D198,making testing in a nonlaboratory environment more feasible.Thus the test methodscan be used on production sites for field testing and quality control,as well as in laboratories forresearch applications.Key differences from Test Methods D198 are the testing speed,the deflection-measuring procedures for test specimens under load,and the detail of data reporting.Furthermore,thetest methods do not require that specimens be loaded to failure.Since these test methods allow latitude in testing procedures,the procedures used shall be fullydocumented in the test report.It may also be desirable to correlate the results from tests carried outaccording to these test methods with test results obtained through the use of a traditional procedure,such as that set forth in Test Methods D198.1.Scope1.1 These test methods cover the determination of themechanical properties of stress-graded lumber and other wood-base structural material.1.2 These test methods appear in the following order:SectionBending edge-wise6Bending flat-wise:Center point loading7Third point loading8Axial strength in tension9Axial strength in compression101.3 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 standard 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:2D9 Terminology Relating to Wood and Wood-Based Prod-uctsD198 Test Methods of Static Tests of Lumber in StructuralSizesD2915 Practice for Sampling and Data-Analysis for Struc-tural Wood and Wood-Based ProductsD4442 Test Methods for Direct Moisture Content Measure-ment of Wood and Wood-Base MaterialsD7438 Practice for Field Calibration and Application ofHand-Held Moisture MetersE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE177 Practice for Use of the Terms Precision and Bias inASTM Test Methods1These test methods are under the jurisdiction of ASTM Committee D07 onWood and are the direct responsibility of Subcommittee D07.01 on FundamentalTest Methods and Properties.Current edition approved April 1,2013.Published May 2013.Originallyapproved in 1988.Last previous edition approved in 2011 as D4761 11.DOI:10.1520/D4761-13.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.2 Other Document:3NIST Voluntary Product Standard PS20 American SoftwoodLumber StandardNOTE1The current version of PS20 is given as an example of aproduct standard applicable to stress-graded lumber.Other product stan-dards may apply to stress-graded lumber.For wood-base structuralmaterials other than stress-graded lumber,relevant product standards mayapply.3.Terminology3.1 DefinitionsSee Terminologies D9 and E6 and Prac-tices E4 and E177 for definitions of terms used in these testmethods.3.2 Definitions of Terms Specific to This Standard:3.2.1 breadththat dimension of the test specimen in thedirection perpendicular to the span and perpendicular to thedirection of an applied bending load.3.2.2 depththat dimension of the test specimen in thedirection perpendicular to the span and parallel to the directionof an applied bending load.3.2.3 spanthe distance between the center lines of thepivot points upon which the test specimen is supported toaccommodate a transverse bending load or,for tension loading,the distance between the grips.4.Significance and Use4.1 These test methods provide procedures that are appli-cable under true field con