1、Designation:D199014Standard Practice forEstablishing Allowable Properties for Visually-GradedDimension Lumber from In-Grade Tests of Full-SizeSpecimens1This standard is issued under the fixed designation D1990;the number immediately following the designation indicates the year oforiginal adoption or
2、,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.INTRODUCTIONVisual stress-grades of lumber manufactured in North America have evolved from the pr
3、oceduresof Practice D245.Allowable stress and modulus of elasticity values were determined for these gradesusing the procedures of Practice D245 and the appropriate clear wood values of Practice D2555.Theclear wood values of Practice D2555 were developed from tests of small clear specimens.Developme
4、nt of allowable stress and modulus of elasticity values from tests of full-size structurallumber as commercially produced and marketed has become possible with the development of suitabletest equipment that permits rapid rates of loading to test large numbers of pieces from commerciallumber producti
5、on.These tests can be carried out at the production sites or in a laboratory.1.Scope1.1 This practice covers the principles and procedures forestablishing allowable stress values for bending,tension par-allel to grain,compression parallel to grain and modulus ofelasticity values for structural desig
6、n from“In-Grade”tests offull-size visually graded solid sawn dimension lumber.Thispractice also covers procedures for periodic monitoring,andadditional procedures,if needed,for evaluation and possiblereassessment of assigned design values.This practice is fo-cused on,but is not limited to,grades whi
7、ch used the conceptsincorporated in Practice D245 and were developed and inter-preted under American Softwood Lumber PS 20.1.2 A basic assumption of the procedures used in thispractice is that the samples selected and tested are representa-tive of the entire global population being evaluated.Thisapp
8、roach is consistent with the historical clear wood method-ology of assigning an allowable property to visually-gradedlumber which was representative of the entire growth range ofa species or species group.Every effort shall be made to ensurethe test sample is representative of population by grade an
9、dsize(see 7.1.1 and 7.1.2).1.3 Due to the number of specimens involved and thenumber of mechanical properties to be evaluated,a methodol-ogy for evaluating the data and assigning allowable propertiesto both tested and untested grade/size cells is necessary.Sampling and analysis of tested cells are c
10、overed in PracticeD2915.The mechanical test methods are covered in TestMethods D198 and D4761.This practice covers the necessaryprocedures for assigning allowable stress and modulus ofelasticity values to dimension lumber from In-Grade tests.Thepractice includes methods to permit assignment of allow
11、ablestress and modulus of elasticity values to untested sizes andgrades,as well as some untested properties.The practiceincludes procedures for periodic monitoring of the species orspecies group to quantify potential changes in the product andverification of the assigned design values through,evalua
12、tion,and reassessment.NOTE1In the implementation of the North American In-Grade testprogram,allowable stress values for compression perpendicular to grainand shear parallel to grain for structural design were calculated using theprocedures of Practice D245.1.4 This practice only covers dimension lum
13、ber.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is the1This practice is under the jurisdiction of ASTM Committee D07 on Wood andis the direct responsibility of Subcommittee D07.02 on Lumber and EngineeredWood Products.Current edition appr
14、oved Feb.15,2014.Published April 2014.Originallyapproved in 1991.Last previous edition approved in 2007 as D1990 07.DOI:10.1520/D1990-14.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 responsibility of the user of this standard to establ
15、ish 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 StructuralSizesD245 Practice for Estab
16、lishing Structural Grades and Re-lated Allowable Properties for Visually Graded LumberD1165 Nomenclature of Commercial Hardwoods and Soft-woodsD2555 Practice for Establishing Clear Wood Strength ValuesD2915 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-Based MaterialsD4444 Test Method for Laboratory Standardization andCalibration of Hand-Held Moisture MetersD4761 Test Methods for Me
