1、Designation: D 3535 07aStandard Test Method forResistance to Creep Under Static Loading for StructuralWood Laminating Adhesives Used Under Exterior ExposureConditions1This standard is issued under the fixed designation D 3535; the number immediately following the designation indicates the year ofori
2、ginal 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 adhesives suitable for thebonding of
3、wood, including treated wood, into structurallaminated wood products for general construction, for marineuse, or for other uses where a high-strength general construc-tion, creep-resistant, waterproof adhesive bond is required.1.2 The values stated in SI units are to be regarded as thestandard. The
4、values given in parentheses are for informationonly.1.3 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
5、 regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A 125 Specification for Steel Springs, Helical, Heat-TreatedD 907 Terminology of AdhesivesD 2559 Specification for Adhesives for Structural Lami-nated Wood Products for Use Under Exterior (Wet Use)Exposure Conditions3. T
6、erminology3.1 Definitions:3.1.1 glulam, nsynonym for structural-glued-laminatedtimber.3.1.2 structural-glued-laminated timber, nan engineered,stress-rated product of a timber laminating plant comprisingassemblies of specially selected and prepared wood lamina-tions securely bonded together with adhe
7、sives, with the fol-lowing characteristics: (1) the grain of all laminations isapproximately parallel longitudinally; and (2) the laminationsmay be comprised of pieces end-joined to form any length, ofpieces placed or glued edge-to-edge to make wider ones or ofpieces bent to curved form during gluin
8、g. (Synonym glulam)ANSI/AITC A190.1 2002, American National Standard forWood ProductsStructural Glued Laminated Timber (Editedto conform with ASTM format).3.1.3 For other terms used in this test method, refer toTerminology D 907.4. Summary of Test Method4.1 Glued laminations are subjected to a const
9、ant load undervarious combinations of temperature and relative humidity.The amount of creep is measured.5. Significance and Use5.1 This test method rates the performance of the adhesivein laminated wood as measured by resistance to creep understatic load.5.2 This test method will normally be used in
10、 conjunctionwith Specification D 2559.6. Apparatus6.1 Compression-Type Creep Tester, as shown in Fig. 1,3required for testing the specimens under the static load. Thistester consists of:6.1.1 Base Plate,6.1.2 Four Tension Rods,6.1.3 Spacer Plate,6.1.4 Center Rod,6.1.5 Spring,6.1.6 Top Plate, and6.1.
11、7 Nuts.6.2 Metal Spacers, coated with an effective mold-releaseagent. Seven are needed for each laminate. Dimensions are69.8 mm (234 in.) long by 15.9 mm (58 in.) wide by 6.4 mm (141This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subco
12、mmittee D14.30 on WoodAdhesives.Current edition approved May 1, 2007. Published May 2007. Originallyapproved in 1976. Last previous edition approved in 2007 as D 3535 07.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annu
13、al Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Springs selected must fit within the space provided approximately 110-mm(4.3-in.) maximum outside diameter and 300-mm (11.8-in.) maximum overallheight and should be of corrosion-resistant ma
14、terial (for example, stainless steel,cadmium, or zinc-plated steel), should have a spring constant of 35 000 6 7000N/m (200 6 40 lbf/in.) and a load when fully compressed (that is at solid height) ofabout 4500 N (approximately 1000 lbf). For additional information, refer toSpecification A 125 for St
15、eel Springs, Helical, Heat Treated.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Metric Equivalentsmm in. mm in.3.1818 127 54.77316 139.7 5129.5338 148 53411.1716 165.1 61215.958 267 101219.134 304.8 1225.4 1 311.1 121438.1 112 336
16、.5 131454.0 218 415 163860.3 238 660.4 2663.5 212FIG. 1 Compression-Type Creep Tester3D 3535 07a2in.) thick. Spacers made of other materials may also be usedprovided it does not react with the adhesive and can beremoved without disturbing the specimen.6.3 Oven, capable of maintaining 71 6 2C (160 6
17、3.6F)and humidity chamber capable of maintaining 26.7 6 2C (806 3.6F) and 90 6 5 % relative humidity.NOTE 1Some ovens may not be able to accommodate a full lengthcreep tester. Since the test specimen is 276 mm in length, it is permissibleto reduce the “ filler pieces” and angles to a length of 267 m
18、m eachallowing pressure to be exerted directly on the test specimen without theuse of filler blocks. Fig. 2 shows an optional creep tester. The changes areto the lengths of the 4-tension rods, center rod, angles and filler pieces.Use of this tester requires special care when choosing a spring (seefo
19、otnote 3 in Fig. 1 and 10.1) that will fit the reduced space. All othermeasurements will be the same as Fig. 1.7. Selection and Preparation of Wood7.1 Use any softwood or hardwood planned for gluing. Onlyone species is required, even if several will be glued. Flat-grained wood is most desirable, how
20、ever experience has shownthat flat-grained specimens may break in the wood whenloaded. (This test measures only creep. Use SpecificationD 2559 to measure bondability to all species considered.)7.2 The wood shall have a slope of grain not steeper than 1in 15 on any face or any edge. The wood shall co
21、ntain no knotslarger than 3.18 mm (18 in.) in diameter and shall be free ofFIG. 2 Optional Compression-Type Creep TesterD 3535 07a3decay, machining defects (such as chipped grain, dubbed ends,feed roll polish, coarse knife marks, and feed roll compres-sion), and any drying defects such as case harde
22、ning, collapse,splits, or checks.7.3 Condition the wood at 23 6 2C (73.4 6 3.6F) and arelative humidity of 50 to 70 % (preferably 65 %) until amoisture content of 8 to 14 % or, preferably, 9 to 12 % has beenobtained.7.4 Freshly knife plane each lamination before applying thetest adhesive. The machin
23、ing tolerances for each laminationused in preparing the test specimen shall be no greater than60.25 mm (0.01 in.) between laminations and 60.20 mm(0.008 in.) within laminations. Observe the most severe of theabove tolerances.8. Test Specimens8.1 The laminated wood members shall be prepared fromboard
24、s 15.9 mm (58 in.) thick by 63.5 mm (212 in.) wide by304.9 mm (12 in.) along the grain for each test condition. Eachtest lamination shall be made from two outer laminations asabove and alternate metal spacers and wood sections for theinner lamination (Fig. 3). The wood sections shall be slicedfrom a
25、 third board identical to that above. The wood sectionsshall be 28.5 mm (118 in.) along the grain by 15.9 mm (58 in.)thick by 63.5 mm wide. The laminated wood members shall beprepared by alternately laying seven metal spacers on edgetightly adjacent to eight wood center sections. The woodsections sh
26、ould be slightly thicker than the metal spacers toobtain adequate pressure on the gluelines. It has been foundthat running a 13-mm (12-in.) piece of tape completely aroundthe 16 loose pieces holds them together as a unit while gluing.Glue should be applied to the outer laminations and not thecenter
27、ply. The outer laminations shall then be applied over-lapping about 13 mm on each end and the entire assemblycarefully clamped and the adhesive cured as recommended.After curing and clamp removal, the metal spacers shall bepushed gently (not impact driven) out. Then each three-plylaminated wood memb
28、er shall be trimmed along the sides toleave a width of 50.8 6 0.8 mm (2 6132 in.) and the outeroverlapping boards at one end trimmed to 3.2 mm (18 in.)longer than the inner section. A center line perpendicular to thegrain shall be marked across all of the 28.6-mm center sectionsand running to the sp
29、ecimen edge. The specimen shall then benotched as in Fig. 3, the 3.2-mm notches being visuallycentered on the above lines. Notching should be to, but notbeyond, the adhesive line. The specimen shall then be trimmedat the untrimmed end to 276.2 mm (1078 in.). This dressedmember, 47.6 by 50.8 by 276.2
30、 mm (178 by2by1078 in.)appears in Fig. 3. When the specimen is loaded axially, shearloads shall be applied to the 15 overlap areas which are 50.8 by12.7 mm (2 by 0.5 in.), giving double leg joints with gluelinearea of 1290 mm2(2 in.2).8.2 Two specimens for each variable combination to beinvestigated
31、 are prepared.9. Assembly Time9.1 Only one combination of open and closed assembly timeis required. The open and closed assembly times are to be theoptimum recommended with the adhesive manufacturers in-structions.10. Procedure10.1 Preparatory to testing, use a square and razor blade toscribe a line
32、 perpendicular to the exposed gluelines across eachof the lapped areas. Then insert the stack of test specimenswithin the guides of the compression-type creep tester de-scribed in 6.1 and shown in Fig. 1 and position spacer plate No.2 on top. (In case the stack of specimens does not come to orslight
33、ly above the guides, use filler blocks on top of the stack.)Insert the spring and position spacer plate No. 1 on top of thespring. Exert a gentle compression and position the corner nuts.Load the entire unit in any type of compression testing machinesuch as that described in 6.1 to 218.2 kg (480 lb)
34、 total load1655 kPa (240 psi) and tighten the corner nuts by hand tomaintain spring compression. Position the keeper nut on centerrod and tighten to within 9.5 mm (38 in.) on the top plate, thusretaining the spring in case one or two specimens fail.10.2 Place the entire unit in the test apparatus de
35、scribed in6.3 and condition at one of the following conditions. Preparetwo units for each test condition and adhesive-wood combina-tion.TemperatureRelative Humidity, % Time, daysF C160 71 ambient 780 26.7 90 7FIG. 3 View of Assembled Test BlocksD 3535 07a410.3 MeasurementsAt the end of the 7 days re
36、move thefour test jigs from the oven and humidity chamber. Measure thetotal length slippage (creep) in all gluelines to the nearest 0.127mm (0.005 in.). Add the total length of creep for both testspecimens and each variable combination report in millimetres(inches).11. Report11.1 The report shall in
37、clude the following:11.1.1 Identification of the adhesive used by class, number,or manufacturers mark,11.1.2 Application and bonding conditions used for thespecimen,11.1.3 Wood preparation and conditioning including spe-cific gravity and moisture content at time of bonding,11.1.4 Temperature and rel
38、ative humidity at time of bond-ing,11.1.5 Number of specimens tested, and11.1.6 The creep values obtained.12. Precision and Bias12.1 At the present time, there is no basis for a statement ofprecision or bias concerning the reproducibility of resultsamong laboratories. Such information may be availab
39、le in thefuture following round-robin testing among laboratories.12.2 The precision and bias of this test method is a functionof the properties of the cured bondline; if wood failure occurs,it is a function of the woods variability. Precision shall bereported in terms of the standard deviation of th
40、e data and thestandard error of the mean.13. Keywords13.1 creep; exterior exposure; glulam; structural-glued-laminated timberASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are ex
41、pressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revi
42、sed, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you ma
43、y attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 3535 07a5
