1996 LRFD Manual for Engineered Wood Construction

vGlossaryAdjusted resistance. The reference resistance adjustedto include the effects of all applicable adjustment factorsresulting from end use and other modifying factors. Timeeffectadjustments are not included because they areconsidered separately.American Softwood Lumber Standard. A voluntaryproduct standard developed by the National Institute ofStandards and Technology, U.S. Department of Commerce,in cooperation with wood producers, distributors,and users. The standard establishes the dimensions forvarious types of lumber products, the technical requirementsand the methods of testing, grading and marking,and is designated PS 20-94 (Product Standard 20 issuedin 1994).American Lumber Standard Committee (ALSC). Astanding committee composed of representatives of producers,distributors, specifiers, and consumers of lumber.The primary function of the committee is to review andconsider revisions to the American Softwood LumberStandard, PS 20-94. ALSC inspectors conduct field checkson certified grading agencies and the committee’s independentBoard of Review has the power to discipline underthe aegis of the Commerce Department, National Instituteof Standards and Technology.Aspect ratio. In any rectangular configuration, the ratioof the long side’s length to the short side’s length.Assembly. A collection of parallel structural membersand/or components connected in a manner such that loadapplied to any one component will affect the stress conditionsof adjacent parallel components.Assembly effects. Component interactions that affect theway stress is distributed within an individual componentand/or the way loads are distributed to other componentsin an assembly.Boundary elements. Shear wall and diaphragm membersto which sheathing transfers forces. Boundaryelements include chords and drag struts at shear wall anddiaphragm perimeters, interior openings, discontinuitiesand reentrant comers.Built-up member. A member made of structural woodelements that are glued or mechanically connected.Clear span. Inside distance between the faces of supports.Composite action. Interaction between elements connectedin such a way that the resulting member strengthand stiffness is greater than the sum of the strength andstiffness of the individual elements.Composite member. A member composed of multipleelements connected so as to achieve composite action.Composite panel. A structural-use panel comprised ofwood veneer and reconstituted woodbased material andbonded with waterproof adhesive.Connection. An attachment used to transmit forces betweentwo or more members by means of a fastener, anassembly of fasteners, or adhesive, acting alone or in combinationwith member bearing.Connector. Synonym for fastener.Decay. Decomposition of wood substance caused by actionof wood-destroying fungi; the word “rot” means thesame as decay.Decking. Solid sawn lumber or glued laminated deckingexpressed in nominal terms as being “2 in. to 4 in.” thickand “4 in. and wider.” Decking is usually surfaced to singletongue and groove in 2 in. (51 mm) nominal thickness. In3 in. (76 mm) and 4 in. (102 mm) nominal thickness, itmay be double tongue and groove and worked withrounded or V edges, striated, or grooved.Design resistance. Resistance (force or moment as appropriate)provided by member or connection; the productof adjusted resistance, the resistance factor, and time-effectfactor.Design span. For simple, continuous, and cantileverbeams, the design span is the clear span plus one-half therequired bearing length at each support.Design strength. Material strength (tensile, compressive,etc.) derived in accordance with ASTM 5457-93 proceduresand adjusted to reflect end-use conditions.Diaphragm. A sheathed horizontal or nearly horizontalsystem (e.g., roof, floor) acting to transfer lateral forcesto the vertical resisting elements.AMERICAN FOREST & PAPER ASSOCIATION