1、Designation: D2523 13Standard Practice forTesting Load-Strain Properties of Roofing Membranes1This standard is issued under the fixed designation D2523; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice is a guide for determining the load-strainproperties of roofing membranes and their components atvarious temperatures. Tes
3、t specimens may be prepared in thelaboratory or cut from samples obtained in the field.1.2 The values stated in SI units are to be regarded as thestandard. The inch-pound units given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if an
4、y, 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:2D95 Test Method for Water in Petroleum Products an
5、dBituminous Materials by DistillationD412 Test Methods for Vulcanized Rubber and Thermoplas-tic ElastomersTensionE178 Practice for Dealing With Outlying Observations3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 roofing membranethat part of the roofing systemwhose primary fun
6、ction is to exclude water; it does not includefield-applied aggregate.4. Significance and Use4.1 This practice is designed to aid those interested in theengineering properties of roofing membranes.4.2 The data obtained will not permit prediction of theservice life of a membrane under field condition
7、s. The data willprovide a basis for study of the mechanical properties of themembrane. Note that if strain rates, specimen dimensions,initial clear distance between clamps, or temperatures andmoisture contents are varied, the data may not be strictlycomparable.5. Sampling5.1 Take field membrane samp
8、le at least 100 by 250 mm (4by 10 in.) in accordance with good roofing practices. In caseswhere field-applied aggregate is in place, remove it with ascraper such as a heated putty knife.5.1.1 Sample those areas of the membrane that are expectedto represent the extremes in load/strain characteristics
9、.5.1.2 At least one sample is required for each test tempera-ture at which it is desired to determine load/strain properties.5.2 Prepare laboratory samples at least 200 by 300 mm (8by 12 in.) in strict accordance with the roofing specificationbeing tested. Observe all cautions specified, such as not
10、overheating the bitumen. Do not oven condition any of thecomponents or the final sample.5.2.1 Select those areas of the membrane that are expectedto represent the extremes in load-strain characteristics. Prepareat least one sample of each type for each proposed testtemperature. If there is any doubt
11、 about these areas, include allpossible variations. The samples must be uniform in crosssection.5.2.2 Select materials at random when possible. Compo-nents should be conditioned at 50 6 5 % relative humidity and25 6 2.5C (77 6 4.5F) for 24 h prior to constructingsamples.5.2.3 The quantity of materia
12、l in any layer should be within610 %, and the entire sample should be within 65 % of thequantities specified.6. Test Specimens6.1 Condition the samples at room temperature at 50 6 5%relative humidity for a minimum of 16 h for non-solvent-containing membranes, and until constant mass has beenreached
13、for solvent-containing membranes.6.2 Die-cut three tension test specimens from each sample.The shape of the specimens for membranes with less than 50 %ultimate elongation is shown in Fig. 1. Where the membranehas an ultimate elongation greater than 50 %, use Die C of TestMethods D412.1This practice
14、is under the jurisdiction ofASTM Committee D08 on Roofing andWaterproofing and is the direct responsibility of Subcommittee D08.20 on RoofingMembrane Systems.Current edition approved June 15, 2013. Published July 2013. Originallyapproved in 1966. Last previous edition approved in 2006 as D2523 00 (2
15、006).DOI: 10.1520/D2523-13.2For referenced 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
16、Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.3 At least three specimens must be tested at each selectedtemperature from each sample. If any sample is too small topermit the removal of three specimens, more than one sampleof that type must be prepared or obtained
17、in the field to yieldthe required three specimens.7. Procedure7.1 Condition each specimen at least1hattheselected testtemperature.7.2 Control the following standard test temperatures to atolerance of 62.5C (4.5F): 18C (0F), 0C (32F), and25C (77F). Recommended additional test temperatures,where appro
18、priate, are: 34.4C ( 30F), 50C (122F) and70C (158F).7.3 Use a tension testing machine, preferably with auto-matic load and strain recording equipment, and clamps thatpermit a uniform clamping pressure on the specimen withoutslipping. The clamps should be 178 6 5mm(76 0.2 in.) apartat the start of th
19、e test.7.4 Maintain a rate of elongation of 1.0 6 0.3 %/min forbituminous membranes or other materials having under 50 %ultimate elongation. This rate will be achieved if the jaws areseparated at 1.3 mm/min (0.05 in./min).7.5 Use a rate of elongation of 500 mm/min (20 in./min) formembranes whose ult
20、imate elongation exceeds 50 %.7.6 Measure the elongation of dumbbell specimens as thechange in distance between reference marks on the constrictedarea of the specimen (see Fig. 1). Discard all specimensbreaking outside the reference marks.7.7 Test a minimum of three specimens from each sample ateach
21、 selected temperature.7.8 Measure the moisture content of broken bituminousmembrane specimens in accordance with Test Method D95.8. Calculation8.1 Calculate the strain by the following equation:s 5 100c 2 c0!/c0(1)where:s = specimen strain, %,c0= distance between reference marks before application o
22、fload, andc = distance between reference marks at a given load.8.2 Calculate the load/strain modulus by dividing one halfthe maximum load per unit specimen width by the strain at thatload in consistent units. Due to the difficulty of measuring thethickness of roofing membranes, and their nonhomogene
23、ity,loads should be reported in force per unit specimen width.9. Report9.1 Report the following information:9.1.1 Source and type of all components of the membrane,9.1.2 Specification for the membrane tested,9.1.3 Details of sample construction, including componentorientation and dimensions, specime
24、n shape, test temperature,rate of strain, number of specimens tested, and moisturecontent,9.1.4 Strain corresponding to each increase in load of 1.75kN/m (10.0 lbf/in.) for each specimen,9.1.5 Load and strain at failure for each specimen,9.1.6 Load - strain diagram and modulus for each specimen,and9
25、.1.7 Compute and report the average of all tests onspecimens from each sample at each temperature. Disregardindividual values exceeding the 5 % level of significance asdefined and computed in Practice E178, and compute a newaverage without them. The new average must be based on notless than three te
26、sts, and preferably more. Comment on anyobservable factors which may have contributed to large differ-ences from the average.10. Keywords10.1 elongations; load-strains; moisture contents; roofingmembranes; temperaturesNOTE 1All dimensions are in millimetres.FIG. 1 Tension Test Specimen.D2523 132ASTM
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28、irely 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 revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsan
29、d should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee o
30、n 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D2523 133
