1、Designation: D5055 10Standard Specification forEstablishing and Monitoring Structural Capacities ofPrefabricated Wood I-Joists1This standard is issued under the fixed designation D5055; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.1. Scope1.1 GeneralThis specification gives procedures for estab-lishing, monitoring, and reevaluating structural c
3、apacities ofprefabricated wood I-joists. Capacities considered are shear,reaction, moment, and stiffness. Procedures for establishingcommon details are given and certain design considerationsspecific to wood I-joists are itemized.1.2 Contents of the StandardAn index and brief descrip-tion of the mai
4、n features of this specification are given inX1.1.1.1.3 Development of the StandardThe development andintent of this specification is discussed in Appendix X1.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI un
5、its that are provided for information onlyand are not considered standard.1.5 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
6、 the applica-bility of regulatory limitations prior to use. A specific precau-tionary statement is given in 6.1.1.5.2. Referenced Documents2.1 ASTM Standards:2D198 Test Methods of Static Tests of Lumber in StructuralSizesD245 Practice for Establishing Structural Grades and Re-lated Allowable Propert
7、ies for Visually Graded LumberD1990 Practice for Establishing Allowable Properties forVisually-Graded Dimension Lumber from In-Grade Testsof Full-Size SpecimensD2559 Specification for Adhesives for Structural Lami-nated Wood Products for Use Under Exterior (Wet Use)Exposure ConditionsD2915 Practice
8、for Evaluating Allowable Properties forGrades of Structural LumberD4761 Test Methods for Mechanical Properties of Lumberand Wood-Base Structural MaterialD5456 Specification for Evaluation of Structural CompositeLumber ProductsD5457 Specification for Computing Reference Resistanceof Wood-Based Materi
9、als and Structural Connections forLoad and Resistance Factor DesignD7247 Test Method for Evaluating the Shear Strength ofAdhesive Bonds in Laminated Wood Products at ElevatedTemperaturesD7480 Guide for Evaluating the Attributes of a ForestManagement PlanE4 Practices for Force Verification of Testing
10、 MachinesE529 Guide for Conducting Flexural Tests on Beams andGirders for Building ConstructionE699 Practice for Evaluation of Agencies Involved in Test-ing, Quality Assurance, and Evaluating of Building Com-ponentsIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI): The Modern
11、 Metric System2.2 U.S. Product Standards:3PS-1 Structural PlywoodPS-2 Performance Standard for Wood-Based Structural-UsePanelsPS-20 American Softwood Lumber Standard2.3 Other Standards:CSA O86 Engineering Design in Wood4CSA Standards for Wood Adhesives O112 Series4CSA O121 Douglas-fir Plywood4CSA O1
12、41 Softwood Lumber4CSA O151 Canadian Softwood Plywood4CSA O325 Construction Sheathing4CSA O437.0 OSB and Waferboard41This specification is under the jurisdiction of ASTM Committee D07 on Woodand is the direct responsibility of Subcommittee D07.02 on Lumber and EngineeredWood Products.Current edition
13、 approved Jan. 1, 2010. Published January 2010. Originallyapproved in 1990. Last previous edition approved in 2009 as D5055 09. DOI:10.1520/D5055-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
14、rds volume information, refer to the standards Document Summary page onthe ASTM website.3Available from APAThe Engineered Wood Association, 7011 South 19thStreet, Tacoma, WA98466, http:/www.apawood.org; and TECO, 2902 Terra Court,Sun Prairie, WI 53590, http:/.4Available from Canadian Standards Assoc
15、iation (CSA), 5060 Spectrum Way,Mississauga, ON L4W 5N6, Canada, http:/www.csa.ca.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Lumber Grading Rules Approved by American LumberStandards Committee (ALSC) or Canadian Lumber Stan-dard
16、s Accreditation Board (CLSAB)5SPS-1 Fingerjoined Structural Lumber6SPS-4 Fingerjointed Flange Stock Lumber, 200163. Terminology3.1 Definition:3.1.1 prefabricated wood I-joista structural membermanufactured using sawn or structural composite lumberflanges and structural panel webs, bonded together wi
17、th exte-rior exposure adhesives, forming an “I” cross-sectional shape.These members are primarily used as joists in floor and roofconstruction.3.2 Definitions of Terms Specific to This Standard:3.2.1 capacity (or structural capacity)the numeric resultof certain calculations specified in this specifi
18、cation.3.2.2 design valuethe numeric value claimed by themanufacturer as appropriate for use in structural analysis.NOTE 1A brief discussion of this issue is found in X1.9.3.2.3 structural composite lumbera composite of woodelements (for example, wood strands, strips, veneer sheets, ora combination
19、thereof), bonded with an exterior grade adhesiveand intended for structural use in dry service conditions.4. Design Considerations4.1 Design Value Adjustments:4.1.1 Duration of LoadWith the exception of reactiondesign values limited by compression perpendicular to grain,prefabricated wood I-joists s
20、hall be designed using the strengthadjustment for load duration used in sawn lumber. Thisadjustment is determined in accordance with the section onDuration of Load Under Modification of Allowable Propertiesfor Design Use in Practice D245.4.1.2 Repetitive MembersThe repetitive member factorfor prefab
21、ricated I-joists shall be taken as 1.0.NOTE 2Committee D07 chose to reduce the repetitive member factorto unity primarily for purposes of design simplicity. A discussion of thisdecision is given in Appendix X1.4.1.3 TreatmentsSome pressure treatments affect materialstrength and the quality of prefab
22、ricated wood I-joists. TreatedI-joists shall not be used without evaluation of such effects.4.1.4 EnvironmentThe capacities developed in this speci-fication are applicable to joists used under dry conditions suchas in most covered structures.Appropriate adjustments for usesin other environments shal
23、l be made.4.2 Shear Design:4.2.1 Neglecting loads within a distance from the supportequal to the depth of the member shall not be permitted.4.2.2 Adjustments to the shear design value near the supportor at locations of continuity or where reinforcements areprovided must be substantiated by independe
24、nt testing to thegeneral intended criteria for shear capacity herein.5. Materials5.1 GeneralThe following I-joist components meet thedefinition of a biobased product in accordance with 3.1.2.1 ofGuide D7480:5.1.1 Lumber flange materials complying with USDOCPS-20, CSA O141, NLGA SPS-1, or NLGA SPS-4.
25、5.1.2 Structural composite lumber flange materials comply-ing with Specification D5456.5.1.3 Web materials complying with USDOC PS-1, US-DOC PS-2, CSA O121, CSA O151, CSA O325,orCSA O437.0.5.2 Flange Stock:5.2.1 All flange material shall conform to the requirementsof 6.4. In addition, when the flang
26、e material is structuralcomposite lumber, the following properties shall be determinedin accordance with Specification D5456: modulus of elasticity(flat or edge, depending on flange orientation in the I-joist),compression (parallel and perpendicular to grain), and naildesign values.5.2.2 End joints
27、in purchased flange stock are permittedprovided such joints conform to the general intent and Section10 of this specification.5.3 Web MaterialPanels shall conform to manufacturingor performance standards recognized by the applicable govern-ing code. Examples are PS-1 (or CSA O151) and PS-2 (orCSA O3
28、25). In addition, all panels shall meet the equivalent ofExposure I requirements as specified in PS-1 or PS-2.5.4 AdhesivesAdhesives used to bond together compo-nents of the finished product shall conform to the requirementsin Specification D2559 (or, in Canada, shall conform to anappropriate standa
29、rd from the CSA Standards for Wood Adhe-sives, O112 Series, stipulated in CSA O86). In addition,adhesives used for web-to-web, web-to-flange, and flange-to-flange joints shall be qualified for heat durability performancein accordance with 5.4.3. Appendix X3 gives additional infor-mation and standard
30、s that shall be considered when qualifyingadhesives and adhesive-bonded materials.NOTE 3Heat durable performance implies that a bonded joint willexhibit similar material resistance to solid wood in an elevated tempera-ture environment where the wood material surrounding the joint does notprovide the
31、rmal protection.5.4.1 Adhesives and binder systems used in the fabricationof Structural Composite Lumber products shall be evaluated inaccordance with Specification D5456.5.4.2 Adhesives and binder systems used in the fabricationof panel products used as a web shall be evaluated inaccordance with PS
32、-2 (or, in Canada, CSA O325) with theExposure 1 classification.5.4.3 AdhesivesHeat durability:5.4.3.1 Adhesives used for web-to-web, web-to-flange, andflange-to-flange joints shall be qualified for heat durabilityperformance through testing in accordance with Test MethodD7247. The test temperature a
33、nd heat exposure duration forspecimens tested at elevated temperature (7.2 of Test MethodD7247) shall meet the requirements of Items 1, 2, and 3 below.5Available from American Lumber Standard Committee (ALSC), P.O. Box 210,Germantown, MD 20874, http:/www.alsc.org; and Canadian Lumber StandardsAccred
34、itation Board (CLSAB), 960 Quayside Drive, Suite 406, New Westminster,BC V3M 6G2, Canada, http:/www.clsab.ca.6Available from National Lumber Grades Authority (NLGA), 302960 Quay-side Drive, New Westminster, BC V3M 6G2, Canada, http:/www.nlga.org.D5055 102(1) For the bonded specimens, the minimum tar
35、get bond-line temperature shall be 428F (220C). For the matched solidwood control specimens, the minimum target temperature atthe shear plane shall be 428F (220C).(2) The minimum target temperatures of Item 1 shall bemaintained for a minimum of 10 min or until achieving aresidual strength ratio for
36、the solid wood control specimens of30 6 10 %, whichever is longer.(3) Block shear testing shall be conducted immediatelyafter removal from the oven such that the specimen bondline orshear plane temperature does not drop more than 9F (5C)after leaving the oven and prior to failure. This provision iss
37、atisfied when the time interval from the removal of thespecimen from the oven to the failure of the block shearspecimen does not exceed 60 s for each specimen tested andthe room temperature of the test laboratory at the time oftesting is not less than 60F (15.5C).5.4.3.2 For adhesives tested in acco
38、rdance with 5.4.3.1, theresidual shear strength ratio for the bonded specimens, ascalculated in accordance with Test Method D7247, shall beequal to or higher than the lower 95 % confidence interval onthe mean residual shear strength ratio for the solid woodcontrol specimens.6. Qualification6.1 Gener
39、alThis section describes procedures, both em-pirical and analytic, for initial qualification of the structuralcapacities of prefabricated wood I-joists. Qualification is re-quired for certain common details of I-joist application sincethey often influence structural capacities. All capacities are to
40、be reported with three significant digits. Any time significantchanges in joist or application details, manufacturing processesor material specifications occur, qualification is required, as fora new manufacturer or product line.6.1.1 TestingQualification tests shall be conducted orwitnessed by a qu
41、alified agency as defined in 8.1. All testresults are to be certified by the qualified agency.6.1.1.1 Sample SizeThe number of specimens specified in6.2, 6.3, 6.4, 6.5, and 6.6 are minimums. The producer wishingto evaluate the validity of the sample size will find a procedurein 4.7 of Practice D2915
42、.6.1.1.2 Test SpecimensMaterials and fabrication proce-dures of test specimens shall be as typical of intendedproduction as can be obtained at the time of manufacturingqualification specimens. Minimum specimen temperature atthe time of test shall be 40F (4C). Specimens shall be testedat the as-recei
43、ved moisture content.NOTE 4It is desirable to conduct preliminary tests to aid the selectionof representative specimens.6.1.1.3 Test AccuracyTests in accordance with this speci-fication are to be conducted in a machine or apparatuscalibrated in accordance with Practices E4 except that thepercentage
44、error shall not exceed 62.0.6.1.1.4 Test MethodsMethods generally applicable to thefull-section joist tests required herein are in Guide E529, withthe following exceptions: (1) the methods are applicable toboth qualification and quality control, (2) load rate shall be asspecified in the following se
45、ctions, and (3) delays between loadincrements are not required. Required tension and compressiontests shall be substantially in accordance with Test MethodsD198 or Test Methods D4761 with load rates as specified in thefollowing sections. All test report formats and content shall bein keeping with th
46、e intended use of the results and be agreedupon by all involved parties prior to the test.6.1.1.5 Test SafetyAll full-scale structural tests are poten-tially hazardous and appropriate safety precautions must beobserved at all times. One particular concern is the potential forlateral buckling during
47、full-section I-joist tests and appropriatelateral restraint must be maintained at all times.6.2 Shear Capacity Qualification:6.2.1 Initial capacity shall be established from either testresults or calculations. The equations used for the calculationmethod shall be confirmed by a test program; the det
48、ails ofwhich are beyond the scope of this specification. Explanationsof the statistics used in the analysis of test results, with anexample, are given in Appendix X4.6.2.2 Factors which influence shear capacity include webtype, thickness, and grade; web to flange joint; joint type inweb (machined, b
49、utted, glued or not, reinforced, etc.). Eachcombination of these web factors must be tested separately inaccordance with 6.2.3, unless the critical combination in aproposed grouping is first established by test. Flange stiffnessinfluences shear strength: if a range of flange sizes is to be usedwith a given combination of web factors, all sizes must betested unless all values are to be based on tests with thesmallest flange. When a range of species or grades of eithersawn or composite lumber is to be grouped, preliminary t
