1、Designation: D 5664 02Standard Test Method forEvaluating the Effects of Fire-Retardant Treatments andElevated Temperatures on Strength Properties of Fire-Retardant Treated Lumber1This standard is issued under the fixed designation D 5664; the number immediately following the designation indicates th
2、e 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers procedures for obtaining
3、data toassess the initial adjustments to allowable design stresses forlumber treated with candidate commercial fire-retardant (FR)formulations and further procedures for obtaining data toassess the effect of extended exposure to elevated temperatureof 66 6 2C (150 6 4F).1.2 This standard does not pu
4、rport 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:D
5、9 Terminology Relating to Wood2D 143 Methods of Testing Small Clear Specimens of Wood2D 1165 Nomenclature of Domestic Hardwoods and Soft-woods2D 3500 Test Methods for Structural Panels in Tension2D 4761 Test Method for Mechanical Properties of Lumberand Wood-Base Structural Material2D 5516 Test Meth
6、od for Evaluating the Flexural Propertiesof Fire-Retardant Treated Softwood Plywood Exposed toElevated Temperatures2E 84 Test Method for Surface Burning Characteristics ofBuilding Materials3E 176 Terminology of Fire Standards32.2 Other Standards:AWPA C20 LumberFire Retardant Treatment by PressurePro
7、cesses4NFPA 703 Standard for Fire Retardant Impregnated Woodand Fire Retardant Coatings for Building Materials5U.S. Product Standard PS 20 American Softwood LumberStandard63. Terminology3.1 DefinitionsDefinitions used in this test method are inaccordance with Terminologies D 9 and E 176 and Nomencla
8、-ture D 1165.4. Summary of Test Method4.1 The general objectives of this test method are to developdata to adjust allowable design stresses of FR-treated lumberfor the initial effects for the tested FR-formulation(s) and todevelop data on in-service thermal stability after extendedexposure to enviro
9、nmental conditions up to 66 6 2C (150 64F) and $50 % relative humidity.4.2 Procedure 1This procedure uses small clear speci-mens cut from end-matched nominal 2 by 4 (38 by 89-mm)dimension lumber (see Fig. 1) to compare the initial effects offire-retardant treatments to untreated controls for bending
10、,tension parallel, compression parallel, and horizontal shearproperties.4.3 Procedure 2This procedure uses small clear speci-mens cut from end matched nominal 2 by 4 (38 by 89-mm)dimension lumber. This second set of specimens is used toassess the differential trends between end-matched fire-retardan
11、t treated and untreated specimens on bending andtension parallel properties over the course of a prolongedexposure to elevated temperature.4.4 Procedure 3The optional third procedure uses full-sized nominal 2 by 4 (38 by 89-mm) dimension lumber tomodify the small clear specimen results from 4.2 and
12、4.3 forsize effects.1This test method is under the jurisdiction of ASTM Committee D07 on Woodand is the direct responsibility of Subcommittee D07.07 on Fire Performance ofWood.Current edition approved Sept. 10, 2002. Published November 2002. Originallypublished as D 566495. Last previous edition D 5
13、66401a.2Annual Book of ASTM Standards, Vol 04.10.3Annual Book of ASTM Standards, Vol 04.07.4Available from American Wood-Preservers Assoc., P.O. Box 5690, Granbury,TX 760490690.5Available from National Fire Protection Association, P.O. Box 9191, Quincy,MA 02269-9101.6Available from The American Lumb
14、er Standard Committee, P.O. Box 210,Germantown, MD 20875-0210.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Significance and Use5.1 The mechanical properties evaluated by this test methodprovide the following:5.1.1 Data for use
15、in developing modification factors for theallowable design properties of fire-retardant treated lumberwhen used at or near room temperatures (see 6.3).5.1.2 Data for use in developing modification factors forallowable design properties of fire-retardant treated lumberwhen exposed to elevated tempera
16、tures and humidity (see 6.4).5.1.3 Data (optional) for use in modifying these factors forsize effects when fire-retardant treated lumber is used at or nearroom temperature and when exposed to elevated temperaturesand humidity (see 6.5).5.2 Data from the first two procedures in this test method ofeva
17、luation are indicative only for that species.NOTE 1The results of the three listed species (Southern pine, Douglasfir, and either white spruce or a Spruce/Fir mixture) may be used togetherto make inference on untested wood species because the three testedspecies represent the full spectrum of expect
18、ed treatability.5.3 Data from the optional third part of this three-partmethod of evaluation are indicative for all species because it isprimarily used to assess size effects.6. Procedures6.1 Treatment:6.1.1 Pressure treat those pieces designated for treatmentwith the fire-retardant formulation bein
19、g evaluated. The gageretention level of each charge shall not be less than themidpoint of the retention range as specified for the species bythe agency certifying the flame spread index of the treatedlumber. The retention range specified by the certifying agencyshall provide a flame-spread index of
20、25 or less when tested inaccordance with Test Method E 84 for 10 min, show noevidence of significant progression combustion when the test iscontinued for an additional 20-min period and not allowprogression of the flame front beyond a distance of 3.2 m (10.5ft) beyond the centerline of the burners a
21、nytime during the30-min extended test.6.1.1.1 The provisions of 6.1.1 are not intended to preventuse of this test standard when the fire-retardant treatmentsbeing certified are for applications other than those requiringconformance to AWPA Standard C-20, NFPA Standard 703, orsimilar building code re
22、quirements for “fire-retardant-treatedwood” that require the Test Method E 84 test extended to 30min. When alternative performance criteria for the treatmentare being certified, the test report on specimens of thattreatment shall state clearly the alternative performance criteriaand that the treatme
23、nt retention was limited to that required forthe alternative performance criteria.6.1.2 Weigh all treated pieces before and immediately aftertreatment to determine the chemical retention based on thesolution retained and the concentration of chemicals in thesolution. Complete a treating report for e
24、ach charge of materialto document the treating cycle, times, pressures, gage retention,and piece retentions.6.2 Post-treatment Drying:6.2.1 After pressure treatment, kiln dry the treated pieces toa maximum moisture content of 19 % following the standardredrying procedures established for the treatme
25、nt and speciesby the manufacturer. Redry the treated pieces at the manufac-turers maximum specified dry bulb temperature with a minus2C (4F) tolerance for 21 h of the first 24-h period. For theremainder of the drying period, the tolerance shall be minus3C (5F). There is no upper limit on the redryin
26、g temperature.Sticker all test pieces to obtain proper air flow across bothsurfaces and to provide even drying.NOTE 2Research has shown that high kiln drying temperatures canadversely affect the structural properties of wood products. The AmericanWood-Preservers Association (AWPA) and National Fire
27、ProtectionAssociation (NFPA) standards for fire retardant treated wood productslimit kiln dry bulb temperatures. AWPA Standard C20 requires that the drybulb temperature of the kiln not exceed 70C (160F) during any kilndrying of plywood treated with fire retardants. In the case of exteriorfire-retard
28、ants that require curing at higher temperatures, curing after themoisture content is 19 % or less is permitted. However, such elevatedcuring temperatures must not exceed 99C (210F) and the total curingtime must not exceed 48 h. In NFPA Standard 703, the dry bulbtemperature must not exceed 70C (160F)
29、 until the average moisturecontent of the wood has dropped to 25 % or less.NOTE 3To establish the worst-case strength properties of treatedlumber, the laboratory must redry the test material within a small negativetolerance of the maximum temperature used by the manufacturer. There-fore, there is no
30、 upper limit for the temperature used in the tests. If amanufacturer desires to establish conservative property values or providea basis for evaluating production material that exceeds the limit, the testmaterial can be redried at that temperature. A manufacturer then is allowedto determine the nece
31、ssary production schedule for their treatment andequipment or conditions. Thus, a stepped schedule (for example, 10 h at54C (130F), 10 h at 60C (140F); 10 h at 71C (160F), etc.) is allowedFIG. 1 Hypothetical Cutting Patterns to Obtain One Bending, TwoTension Parallel, One Compression Parallel, One B
32、lock Shear,and One Specific Gravity Block from Each 1.2-m (4-ft) LumberSpecimenD5664022by the standard, provided the maximum temperature tolerance require-ment is met. These provisions provide for air-drying production materialprovided the redry conditions in the tests are within the tolerance of th
33、emaximum temperature specified by the manufacturer.6.2.2 Monitor the moisture content of the test pieces duringthe drying cycle by individually weighing representativepieces. Keep a well-documented kiln charge report and kilnrecorder chart showing dry and wet bulb temperatures duringthe redrying per
34、iod.6.3 Procedure 1The first procedure presents a methodol-ogy using small clear wood specimens to assess the initialeffect of fire-retardant treatment on median mechanical prop-erties. The results may be used to adjust the allowable designstresses of lumber based on estimates of median reductions i
35、nbending, tension parallel, compression parallel, and horizontalshear properties using small clear specimens cut from largerend-matched dimension lumber specimens.6.3.1 For each species/species grouping (Southern pine,Douglas fir, and either white spruce or a Spruce/Fir mixture),twenty five (25) 2.4
36、4m (8ft) long, high-grade nominal 2 by4s (38 by 89 mm) shall be obtained and cut into 1.22-m (4-ft)halves. Each specimen shall be marked to identify it with itsmatched-sister(s) specimen(s). For each specimen, one 1.22-m(4ft) half shall be randomly allotted to remain untreated andthe other half assi
37、gned to be treated with the candidatefire-retardant treatment and each half shall be appropriatelymarked.NOTE 4A Spruce/Fir mixture can be obtained by obtaining CanadianSpruce-Pine-Fir and removing the Lodgepole pine and Jack pine, whichcan be visually segregated from the remaining spruces and firs
38、of thisspecific species group. The Lodgepole pine and Jack pine have numerouslongitudinal resin canals that are generally quite evenly distributed in theouter portion of every growth ring. In the four spruces (Black, Engelmann,Red, and White), the longitudinal resin canals are generally sparse. In t
39、hetwo firs (Alpine and Balsam), the longitudinal resin canals are normallyabsent.NOTE 5High Grade is a relative term, but some latitude is requiredbecause it is a common industry practice to group grades for somespecies/species groupings into “and better” categories. If available, SelectStructural o
40、ften is desirable because it provides an adequate yield of smallclear specimens. It should also be noted that initial use of $30 specimenswill usually ensure 25 acceptable specimens when using lower gradeswhich have lower yields.6.3.2 After treating and redrying are completed, each treatedand untrea
41、ted nominal 2 by 4 (38 by 89-mm) piece shall be cutinto small clear specimens as shown in Fig. 1. Care shall betaken to avoid cutting specimens containing strength-reducingcharacteristics such as knots, cross-grain, or slope-of-grain inexcess of 1 in 12. When cutting small test specimens, anoriginal
42、 wide surface shall remain unmachined and eachspecimen shall later be tested so that this surface is exposed tothe greater stress during that particular mechanical test. Eachend-matched treated and untreated specimen shall be testedwith the same relative surfaces in tension and compression.Tension p
43、arallel specimens shall be machined as shown in Fig.2. Horizontal shear specimens shall be machined as shown inFig. 3.6.3.3 After cutting, all specimens (treated and untreated)shall be equilibrated to constant weight at 22 + 5C (72 + 9F)and65+1%relative humidity.6.3.4 Appropriate treated and untreat
44、ed specimens shall bealternately tested in bending, compression parallel, and hori-zontal shear using Methods D 143 and tension parallel usingTest Methods D 3500, but with the exceptions listed in Table 1.6.4 Procedure 2For each species (Southern pine, Douglasfir and white spruce, four sets of 25 en
45、d-matched treated anduntreated small clear bending and tension parallel specimensshall be cut from at least 25 nominal 2 by 4 (38 by 89 mm)2.44-m (8-ft) long pieces. These specimens shall be used toassess the differential effects of exposure to elevated tempera-ture between untreated and FR-treated
46、clear wood specimens.6.4.1 One set of 25 FR-treated and untreated specimens ofeach species shall be used as an unexposed control (that is, 0days of exposure).6.4.2 Three FR-treated and untreated groups of 25 speci-mens of each species shall be exposed in a controlled environ-ment of 66 + 2C (150 + 4
47、F) and 50 % relative humidity.6.4.3 One treated and one untreated group of 25 shall bewithdrawn after 36 +3, 72 +3, and 108 +3 days.6.4.4 Each group of specimens shall be equilibrated toconstant weight at 22 + 5C (72 + 9F) and 65+1%relativehumidity then tested in bending in accordance with MethodsD
48、143 and tension parallel in accordance with Test MethodsD 3500, but with the exceptions listed in Table 1.FIG. 2 Dimensions of the Modified Tension Parallel to GrainSpecimen Using Test Methods D 3500D56640236.5 Procedure 3The optional third procedure expands theresults of the small clear results obt
49、ained in 6.3 and 6.4 toinclude additional information on size effects. It assesses boththe initial effects of fire-retardant treatments on the allowabledesign stresses of lumber and the potential for additionalstrength loss after extended exposure to elevated temperatures.To address the former, bending properties shall be assessedusing matched FR-treated and untreated groups of 50 speci-mens. To address the latter, the differential trend in bendingproperties shall be assessed after 108 days of exposure atelevated temperature using matched lo
