1、Designation: D 4355 07Standard Test Method forDeterioration of Geotextiles by Exposure to Light, Moistureand Heat in a Xenon Arc Type Apparatus1This standard is issued under the fixed designation D 4355; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 Thi
3、s test method covers the determination of the dete-rioration in tensile strength of geotextiles by exposure to xenonarc radiation, moisture, and heat.1.2 The light and water exposure apparatus employs axenon-arc light source.1.3 This standard does not purport to address all of thesafety concerns, if
4、 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:2D 123 Terminology Relating to TextilesD 1898 Pr
5、actice for Sampling of PlasticsD 4439 Terminology for GeotextilesD 5035 Test Method for Breaking Force and Elongation ofTextile Fabrics (Strip Method)G113 Terminology Relating to Natural and ArtificialWeathering Tests of Nonmetallic MaterialsG 141 Guide forAddressing Variability in Exposure Testingo
6、n Nonmetallic MaterialsG 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices That Use Laboratory Light SourcesG 155 Practice for Operating Xenon Arc Light Apparatusfor Exposure of Nonmetallic Materials3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 geo
7、textileany permeable textile material used withfoundation, soil, rock, earth, or any other geotechnical engi-neering related material that is an integral part of a man-madeproduct, structure, or system.3.2 Definitions:3.2.1 For definitions of other textile terms used in this testmethod, refer to Ter
8、minology D 123, for geotextile terms referto Terminology D 4439.3.2.2 The definitions given in Terminology G113are appli-cable to this standard.4. Summary of Test Method4.1 Five specimens of a geotextile for the machine directionand for the cross machine direction are exposed in a xenon arcdevice fo
9、r each of the following times: 0 (control specimens),for 150, 300, and 500 h. The exposure consists of 120-mincycles as follows: 90 min of light only at 65 6 3C uninsulatedblack panel temperature and 50 6 5% relative humidity, fol-lowed by 30 min of light plus water spray.4.2 After each exposure per
10、iod, the specimens are subjectedto a cut or ravel strip tensile test. The average breaking strengthin each direction is compared with the average breakingstrength in each direction of the control specimens. The percentstrength retained is plotted versus exposure period to producea degradation curve
11、for the specimens from each direction.5. Significance and Use5.1 This method is intended to induce property changesassociated with end use conditions, including the effects ofsolar radiation, moisture and heat. The exposure used is notintended to simulate the deterioration caused by localizedweather
12、 phenomena such as atmospheric pollution, biologicalattack, and salt water exposure.5.2 The relation between time to failure in an exposureconducted in accordance with this test method, and service lifein a specific outdoor environment requires determination of anacceleration factor as defined in Te
13、rminology G113. Theacceleration factor is material-dependent and is only valid if itis based on data from a sufficient number of separate exterior1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Pr
14、operties.Current edition approved April 1, 2007. Published May 2007. Originallyapproved in 1984. Last previous edition approved in 2005 as D 4355 05.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
15、rds volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.and laboratory-accelerated exposures so that the results used torelate times to failure in each e
16、xposure can be analyzed usingstatistical methods.NOTE 1An example of a statistical analysis using multiple laboratoryand exterior exposures to calculate an acceleration factor is described byJ. A. Simms.3See Practice G 151 for more information and additionalcautions about the use of acceleration fac
17、tors.5.2.1 The deterioration curve obtained from the results ofthis test method enables the user to determine the tendency ofa geotextile to deteriorate when exposed to xenon arc radiation,water and heat.5.3 Variation in results may be expected when operatingconditions are varied within the accepted
18、 limits of this testmethod. Its intended use is as a qualitative assessment of thepresence of ultraviolet inhibitors, and comparison of thatinfluence between products. However, no inference to the timeof stability should be implied by the test results to the relationbetween time duration and outdoor
19、 exposure.NOTE 2Information on sources of variability and on strategies foraddressing variability in the design, execution and data analysis oflaboratory accelerated exposure tests is found in Guide G 141.5.3.1 If it becomes necessary for the purchaser and seller touse this test method for acceptanc
20、e testing, the statistical bias,if any, between the purchasers and sellers laboratories shouldbe determined. Such comparison is to based on specimensrandomly drawn from the sample of geotextile being evaluated.5.3.2 In such cases, as a minimum, the two parties shouldtake a group of test specimens wh
21、ich are as homogeneous aspossible, and which are from a lot of material of the type inquestion. The test specimens should then be randomly assignedin equal numbers to each laboratory for testing. The averageresults from the two laboratories should be compared usingStudents t-test for unpaired data a
22、nd an acceptable probabilitylevel chosen by the two parties before the testing started. If abias is found, either its cause must be found and corrected, orthe purchaser and the supplier must agree to interpret futuretest results in the light of the known bias.6. Apparatus6.1 Xenon-Arc Apparatus, wit
23、h daylight filters conformingto Practices G 151 and G 155.NOTE 3Previous versions of this standard referenced in Practice G 26which describes specific equipment designs of xenon arc devices. PracticeG 26 has been replaced by Practice G 151, which gives performancecriteria for all devices that use la
24、boratory light sources, plus PracticeG 155, which gives requirements for exposure of nonmetallic materials inxenon arc devices.6.1.1 The apparatus must be capable of exposing the speci-mens to cycles of light only, followed by light and moisture aswater spray.6.2 Strength Testing Apparatus, conformi
25、ng to that de-scribed for a 2-in. cut or ravel strip test, as described in TestMethods D 5035.7. Sampling7.1 Lot SampleAs a lot sample for acceptance testing,take at random the number of rolls of fabric directed in anapplicable material specification or other agreement betweenthe purchaser and the s
26、upplier. Consider rolls of fabric to be theprimary sampling units. If the specification requires samplingduring manufacture, select the rolls for the lot sample atuniformly spaced time intervals throughout the productionperiod.NOTE 4An adequate specification or other agreement between thepurchaser a
27、nd the supplier requires taking into account the variabilitybetween rolls of fabric, and between specimens from a swatch from a rollof fabric, so as to provide a sampling plan with a meaningful producersrisk, consumers risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleT
28、ake for the laboratory sample asample extending the full width of the fabric of sufficientlength along the selvage from each sample roll such that therequirements of 8.1 are met. The sample shall exclude materialfrom the outer wrap of the roll or the inner wrap around thecore unless the sample is ta
29、ken at the production site, at whichpoint inner and outer wrap material may be used.8. Specimen Preparation8.1 Take two, one-metre square portions from the laboratorysample. Each shall be no closer to the selvage than110 thesample width. One is to be used for machine directionspecimens, the other fo
30、r cross machine direction specimens.NOTE 5Since the thickness of a specimen may markedly affect testresults, thickness of the replicate specimens shall be within 6 10% of thenominal dimensions. This is especially important when mechanicalproperties are being investigated.8.2 Use template illustrated
31、 in Fig. 1 to identify potentialspecimens from which the actual specimens are drawn. Toselect these actual specimens randomly draw 20 specimensfrom both the machine and cross directions measuring 50 by150 mm (2 by 6 in.) from the one-metre square portions of eachlaboratory sample as directed in Prac
32、tice D 1898.NOTE 6In the event that roller grips are used to hold the specimens inthe tensile testing machine, specimens must be longer than the 150 mm3Simms, J.A., The Journal of Coatings Technology, Vol 50, 1987, pp. 45-53. FIG. 1 Specimen Selection TemplateD4355072length specified. They shall be
33、of sufficient length to ensure propergripping. The portions of the specimens may be rolled to accommodateplacement in the weatherometer. See Fig. 2 and Fig. 3 for placement ofspecimens in the weatherometer. Please note that the rolled portions of thespecimens shall be protected from exposure to the
34、UV light while in theweatherometer.9. Procedure9.1 Operate the xenon-arc test apparatus as directed inPractices G 151 and G 155. Expose test specimens to thefollowing cycle: 90 min of light only at 65 6 2.5C(149 6 5F) uninsulated black panel temperature, and50 6 5 % relative humidity, followed by 30
35、 min of light andwater spray.NOTE 7Immersion in water during exposure to light is one of themethods specified in Practices G 151 and G 155 for providing moisture tospecimens. It can be substituted for water spray if equivalency isdemonstrated, or the geotextile will be immersed in water in its final
36、installation.9.1.1 Unless otherwise specified, maintain the minimumlevel of irradiance at the control point to produce 0.35 6W(/m2/ nm) at 340 nm. If the exposure device is not equippedwith irradiance control, follow the device manufacturersrecommendations to produce this irradiance. for the equival
37、ent300-400 nm or 300-800 nm broad band irradiances andtolerances, consult the manufacturer for the specification.NOTE 8Practice G 155 does not specify a particular irradiance level.Various options are listed in Table X3.1 of the appendix in Practice G 155.FIG. 2 Roller Grip Specimen Ready for Placem
38、ent in WeatherometerNOTE 1When placing specimens to be tested using roller grips inweatherometer the rolled area in the clamp needs to be protected fromexposure to UV to avoid degredation of this area (see arrow).FIG. 3 Roller Grip Specimen in WeatherometerD4355073However, as the historical records
39、of testing of geotextiles are based on theirradiance of 0.35 W/m2/nm at 340 nm, this shall be the standard for TestMethod D 4355.9.2 Randomly assign five specimens for each direction fromeach laboratory sample to each of the following exposuretimes: 0 (unexposed), 150, 300, and 500 clock hours. Plac
40、efifteen specimens from each direction from each laboratorysample in the apparatus, such that the side most likely to solarradiation will be exposed to radiation in the apparatus.9.3 Rotate the positions of the specimens in accordance withPractice G 155.9.4 At the end of each exposure time, remove t
41、he appropri-ate five specimens for each direction for cut or ravel striptensile testing.NOTE 9Specimens should not be removed from the exposure appa-ratus for more than 24 h and then returned for additional test since thisdoes not produce the same results on some materials as tests fun withoutthis t
42、ype of interruption. Report the elapsed time for any specimens forwhich exposure was interrupted for more than 24 h.9.5 Determine the breaking strength in kilonewtons permetre (pounds-force per inch) of five unexposed (control)specimens and five exposed specimens from each exposuretime interval, for
43、 each direction, from each laboratory sampleas directed in Method D 5035 using a 2-in. width strip, except,a CRE or a CRT type testing machine shall be operated at305 6 10 mm (12 612 in.) unless specified otherwise. Thedistance between clamps shall be 75 6 1mm(36 0.05 in.).There may be no overall co
44、rrelation between the resultsobtained with the CRE machine and the CRT machine.Consequently, these two breaking load testers cannot be usedinterchangeably. In case of controversy, the CRE method shallprevail.10. Calculation10.1 Calculate the average breaking strength for all exposedand unexposed (co
45、ntrol) specimens for each direction.10.2 Calculate the percent loss of strength from the unex-posed specimens for the average results of each exposure timefor each direction.10.3 For the groups of five specimens from the unexposedspecimens and the specimens exposed at various times, calcu-late the s
46、tandard deviation and coefficient of variation for thestrip tensile strength.11. Report11.1 The test report shall include the following information:11.1.1 That the tests were made as directed in Test MethodD 4355,11.1.2 A full description of the specimens and their origin,11.1.3 Any full details of
47、sampling not included in Section7,11.1.4 Any details of specimen preparation not included inSection 8,11.1.5 Type and model of exposure device and light source,11.1.6 Type and age of filters at the beginning of theexposure and whether the filters where changed during expo-sure,11.1.7 If required, ir
48、radiance in W/m2nm, or radiant expo-sure in J/m2, at the sample plane and the wavelength region inwhich the measurements were made,11.1.7.1 Do not report irradiance or radiant exposure unlessdirect measurements were made during exposure,11.1.8 Type of black or white panel thermometer, or both ifused
49、, and exact position of the thermometer if not located onthe specimen plane,11.1.9 Description of specimen repositioning, if used,11.1.10 Exposure periods and the elapsed time for anyspecimens for which the exposure was interrupted for morethan 24 h,11.1.11 The total exposure times, along with the totalirradiance at respective clock hour intervals, and the number ofcycles as defined in 9.1.1,11.1.12 A listing of the test results for the unexposed(control) and for each exposure time, for the machine and crossmachine direction, consisting of individual breaking
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