1、Designation: D5405/D5405M 98 (Reapproved 2015)Standard Test Method forConducting Time-to-Failure (Creep-Rupture) Tests of JointsFabricated from Nonbituminous Organic Roof MembraneMaterial1This standard is issued under the fixed designation D5405/D5405M; the number immediately following the designati
2、on indicates theyear of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers laboratory
3、determination of thetime-to-failure (creep-rupture) of joints fabricated from nonbi-tuminous organic roof membrane material. The test methodcovers both T-peel and lap-shear joints subjected to constanttensile load under controlled environmental conditions. Thejoints, made from either unreinforced or
4、 fabric-reinforcedmembrane material, are prepared in the laboratory or sampledfrom roofs in service.1.2 Sheet materials from which the joints are fabricatedinclude vulcanized rubbers, nonvulcanized polymeric sheets,and thermoplastics. The bonding methods for joint formationinclude the use of liquid-
5、based adhesives, preformed tapes, andthermal and solvent weld processes.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other.
6、 Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 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 an
7、d determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D816 Test Methods for Rubber CementsD907 Terminology of AdhesivesD1079 Terminology Relating to Roofing and WaterproofingD1876 Test Method for Peel Resistance of Adhesives (T-Peel Test)3.
8、Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology D907 and D1079.3.2 Definitions of Terms Specific to This Standard:3.2.1 creep-rupture testa test that measures the time-to-failure of a specimen subjected to a constant load; progressivespecimen deformat
9、ion may also be measured.3.2.2 failurerupture of the bond resulting in completeseparation of its adherends under the test conditions; or,alternatively, rupture of the membrane material away from thebonded section of the test specimen (that is, material rupture).3.2.3 time-to-failurethe period of tim
10、e beginning when ajoint specimen is placed under load and ending when failureoccurs.4. Summary of Test Method4.1 This test method is a creep-rupture test without mea-surement of specimen deformation. The time-to-failure, inhours, of joints fabricated from nonbituminous organic roofmembrane materials
11、 is measured when subject to constantdeadweight loads under controlled temperature and humidityconditions.5. Significance and Use5.1 An important factor affecting the performance of jointsof nonbituminous membranes is their ability to remain bondedover the membranes expected service life. Time-to-fa
12、iluretests provide a means of characterizing the behavior of jointsunder constant load over time.5.2 Creep is a sensitive index of rheological properties thatdepend on material, load, temperature, and time. Time-to-failure data that are obtained over a relatively short time periodcan evaluate one fa
13、ctor affecting a joints ability to withstandstatic loading over a relatively long time period.5.3 Time-to-failure data for joints of nonbituminous organicroof membrane specimens can be used for the following: (1)to1This test method is under the jurisdiction ofASTM Committee D08 on Roofingand Waterpr
14、oofing and is the direct responsibility of Subcommittee D08.18 onNonbituminous Organic Roof Coverings.Current edition approved Nov. 1, 2015. Published November 2015. Originallyapproved in 1993. Last previous edition approved in 2011 as D5405/D5405M 98(2011)1. DOI: 10.1520/D5405_D5405M-98R15.2For ref
15、erenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, Wes
16、t Conshohocken, PA 19428-2959. United States1provide a measure of the load-carrying ability of the joint as afunction of time at various levels of load, temperature, andrelative humidity; (2) to characterize the joint with regard tofactors affecting performance, such as surface preparation ofthe adh
17、erend, solvent-based adhesive thickness and open time,environment during adhesive application and cure, and tem-perature of thermal welding processes; and (3) to compare theeffects of different bonding processes or adhesive bondingmaterials on joint performance.5.4 While it is considered that the re
18、sults obtained by thislaboratory test may afford a measure of the performance ofseams in service, provided that load, temperature, and humidityconditions are known, no direct correlation has been estab-lished.6. Apparatus6.1 Test Chamber, of sufficient size to hold a minimum of 15specimens. The heig
19、ht of the chamber shall be sufficient toallow suspension of the deadweight loads and specimendeformation during testing. The chamber shall be structurallycapable of supporting the loads anticipated during testingwithout appreciable deflection.NOTE 1A minimum height of 600 mm 24 in. is suitable for t
20、hespecimen sizes described in this test method if they are not extremelyextensible. A taller chamber may be needed if they are extremelyextensible.6.1.1 Temperature and Humidity ControlThe control oftemperature and humidity is important, since small changes inthese variables may produce large change
21、s in time-to-failure.The temperature and relative humidity within the chambershall be controlled within 63C 6 5F and 65 % relativehumidity, respectively, over the duration of the test. Anydeviations from these limits shall be given in the test report.The selected temperature and humidity conditions
22、shall beuniform throughout the enclosed space (63C or 65F and65 % relative humidity). If this uniformity is achieved throughmechanical air circulation, it shall not cause the specimens tosway, vibrate, or be otherwise disturbed.NOTE 2Suggested test conditions are as follows: (1) normal ambienttemper
23、ature (approximately 23C or 73F) and humidity (50 % relativehumidity); and (2) extremes to which the seams may be subjected inservice.6.2 Specimen and Load ClampingThe chamber shall beequipped with a means for clamping the joint specimensvertically to the top of the interior of the chamber, or other
24、suitable upper support. Also, a clamp shall be provided tosecure the deadweight loads to the bottom of the jointspecimens. Figs. 1 and 2 show a suggested clamping arrange-ment including the deadweight load.6.3 Deadweight Loads, of appropriate mass (see Section10).NOTE 3It is convenient to have avail
25、able a means of providingvariable loads that may differ from test to test, depending on the propertiesof the joint specimens and test conditions. Hollow pipe nipples containinglead shot and sealed with end caps provide convenient deadweights. Themass of the deadweights is adjusted by adding or remov
26、ing lead shot.6.4 Load Application MechanismThis device allows forplacing all of the joint specimens under load simultaneously.An example of such a device is a large tray, suspended onpulleys, which supports the loads attached to the bottom of thespecimens. Lowering the tray allows all test specimen
27、s anddeadweights attached to them to be suspended freely at once.NOTE 4If each specimen has its own timer device (see 6.5), it is notnecessary to load all specimens simultaneously.6.5 Timer Device, for recording the total time over whicheach individual specimen is under load, or for marking the time
28、at which failure of each specimen occurs. The sensitivity of thetimer shall be as follows:Failure Time Timer Sensitivity#25 h 0.1 min25 and #100 h 0.01 h100 h 0.1 hNOTE 5For investigations involving multiple specimens in thechamber, a computer-controlled timer that records the time-to-failure hasbee
29、n found to be satisfactory. In this case, a micro-electrical circuitconnected to the computer is set up for each specimen. The circuit consistsof a wire loop, of which one segment is a short length of wire (triggerwire) attached to each grip on the test specimen and set to stop thecomputer clock whe
30、n failure occurs. At the point of attachment at the topgrip, the trigger wire is inserted in an electrical connector. When thespecimen fails and the deadweight on the lower grip falls, the trigger wireis pulled from the connector, breaking the circuit and stopping the clock.7. Vibration Control7.1 B
31、ecause the time-to-failure tests are sensitive tovibration, select a location of the testing apparatus for mini-mum disturbance. When a vibration-free location is notavailable, the testing apparatus shall be designed so that thespecimens are isolated from vibration. In addition, precautionsshall be
32、taken to avoid vibration caused by the falling dead-weights at specimen failure. Caution shall be exercised duringtesting to avoid vibration due to normal laboratory activitiessuch as opening and closing doors and bench drawers.FIG. 1 Schematic of a T-Peel Specimen Clamped Under LoadD5405/D5405M 98
33、(2015)2NOTE 6A wire cord, attached to the deadweight and also upperspecimen clamp, minimizes vibration at specimen failure. The cord lengthmust be long enough to allow free fall of the deadweight, but short enoughto prevent it from striking the floor of the test chamber.8. Test Specimens8.1 Laborato
34、ry Specimens:8.1.1 The time-to-failure tests are conducted on eitherT-peel or lap-shear specimens. Test specimen variables that canaffect time-to-failure include, depending on the seam fabrica-tion technique, the method of membrane material surfacepreparation, adhesive thickness, adhesive open time,
35、 pressureapplied during bond formation, thermal weld temperature, andweld equipment speed. Other variables that can affect time-to-failure are time, temperature, and relative humidity of thespecimen cure.8.1.2 T-Peel SpecimensPrepare T-peel test specimens, 125by 25 mm 5 by 1 in., 62 %, as shown in F
36、ig. 3. The lengthof the bond shall be 75 mm 3 in. 62 %. The test specimensmay be cut from a single section prepared by bonding two largepieces of sheet membrane material. If specimens havingdimensions other than those specified are tested, they shall bedescribed in the test report. Prior to bond for
37、mation, preparethe surface of the sheet material according to the membranemanufacturers instructions, or using other methods that shallbe described in the test report. Similarly, form the joint usinga process (that is, adhesive tape, or thermal or solvent weld) inaccordance with the membrane manufac
38、turers instructions, orusing other methods that shall be described in the test report.The use of test specimens whose preparation includes addi-tional materials such as primers or sealants is permissible.When adhesives are used, control the thickness to 620 % ofthe value selected for the test specim
39、ens (see 8.1.5). Label eachspecimen with an identification number.8.1.3 Lap-Shear SpecimensPrepare lap-shear testspecimens, 150 by 25 mm 6 by 1 in., 62 %, as shown in Fig.4. The length of the bonded lap shall be 25 mm 1 in. 62%.If specimens having dimensions other than those specified aretested, the
40、y shall be described in the test report. The sheetsurface preparation and bond formation shall be as given in8.1.2. Label each specimen with an identification number.8.1.4 Specimen CureThe temperature and relative humid-ity conditions under which the test specimens are prepared andcured shall be sel
41、ected by the experimenter and described inthe test report. The temperature and relative humidity shall bemaintained within 63C 65F and 65 % relative humidityof the selected values, respectively.8.1.5 Adhesive ThicknessWhen a liquid-based adhesive ortape is used for bond formation, measure the dry-fi
42、lm adhesiveor tape thickness of each specimen using a convenient labora-tory method. Describe the measurement method in the testreport.NOTE 7One method for controlling the thickness of the liquid-basedadhesive layer is to use a drawdown bar or similar device duringapplication of the adhesive to the
43、membrane sheet. Another method is toapply the wet liquid-based adhesive to the membrane sheet at a coveragequantity based on the solids content of the adhesive. In such cases,FIG. 2 Schematic of a Lap-Shear Specimen Clamped Under LoadFIG. 3 Configuration and Dimensions of a T-Peel SpecimenFIG. 4 Con
44、figuration and Dimensions of a Lap-Shear SpecimenD5405/D5405M 98 (2015)3measurements should be performed to establish the thickness-coveragerelation; if necessary, consult with the membrane manufacturer forassistance in determining coverage quantities that will provide specificadhesive thicknesses.8
45、.2 Field Specimens:8.2.1 T-peel or lap-shear specimens, having the dimensionsgiven in Figs. 1 and 2, respectively, may be prepared fromseams sampled from roofs in service. If the specimens havedimensions other than those given in Figs. 1 and 2, thespecimen dimensions shall be given in the test repor
46、t. In thecase of lap-shear specimens, when the length of the bond isgreater than that given in Fig. 2, precautions must be taken toselect sufficiently high deadloads so that failure will occur in areasonable testing time.8.2.2 Record all available pertinent information, including,but not limited to,
47、 specimen age and type, type of membraneattachment, and location of the roof, in the test report.9. Number of Test Specimens and Bond Strength9.1 Prepare a sufficient number of specimens to conductboth bond strength measurement and time-to-failure tests.NOTE 8A newly prepared joint may change with t
48、ime due tomechanisms such as cure, solvent evaporation, or crystallization. Thisresults in a bond strength that increases with time initially and thenreaches a constant value. In such cases, it is necessary to providetime-to-failure specimens that have been cured over a time periodsufficient that th
49、eir bond strength is constant. Determination of theconstant bond strength will influence the number of specimens necessaryto conduct this test method. Pretesting the bond strength of somespecimens over time is useful to estimate the time at which constantstrength is attained under the cure conditions.9.2 Test the bond strength (see 9.2.1 and 9.2.2) of sets of aminimum of three joint specimens (either T-peel or lap-shear)periodically, and plot the strength results versus time. Use aminimum of four time intervals at least one day apart.
