1、Designation:D736107(Reapproved 2012)Standard Test Method forAccelerated Compressive Creep of Geosynthetic MaterialsBased on Time-Temperature Superposition Using theStepped Isothermal Method1This standard is issued under the fixed designation D7361;the number immediately following the designation ind
2、icates the 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()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers accelerated testing for
3、compres-sive creep properties using the Stepped Isothermal Method(SIM).1.2 The test method is focused on geosynthetic drainagematerials such as HDPE geonet specimens.1.3The SIM tests are laterally unconfined tests based ontime-temperature superposition procedures.1.4 Ramp and Hold(R+H)tests may be c
4、ompleted inconjunction with SIM tests.They are designed to provideadditional estimates of the initial rapid compressive creepstrain levels appropriate for the SIM results.1.5 This method can be used to establish the sustained loadcompressive creep characteristics of a geosynthetic that dem-onstrates
5、 a relationship between time-dependent behavior andtemperature.Results of this method are to be used to augmentresults of compressive creep tests performed at 20 6 1C andmay not be used as the sole basis for determination of longterm compressive creep behavior of geosynthetic material.1.6 The values
6、 stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.7 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 a
7、nd health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1621 Test Method for Compressive Properties of RigidCellular PlasticsD2990 Test Methods for Tensile,Compressive,and FlexuralCreep and Creep-Rupture of PlasticsD4439
8、Terminology for GeosyntheticsD5262 Test Method for Evaluating the Unconfined TensionCreep and Creep Rupture Behavior of GeosyntheticsD6364 Test Method for Determining Short-Term Compres-sion Behavior of Geosynthetics3.Terminology3.1 Definitions:For definitions related to geosynthetics seeTerminology
9、 D4439.3.2 Definitions:For definitions related to creep see TestMethods D2990,D5262 and D4439.3.3 Definitions of Terms Specific to This Standard:3.3.1 viscoelastic responserefers to polymeric creep,strain,stress relaxation or a combination thereof.3.3.2 compressive creeptime-dependent deformation th
10、atoccurs when a specimen is subjected to a constant compressiveload.3.3.3 time-temperature superpositionthe practice of shift-ing viscoelastic response curves obtained at different tempera-tures along a horizontal log time axis so as to achieve a mastercurve covering an extended range of time.3.3.4
11、shift factorthe displacement along the log time axisby which a section of the creep or creep modulus curve ismoved to create the master curve at the reference temperature.Shift factors are denoted by the symbol when the displace-ments are generally to shorter times(attenuation)or the symbolaTwhen th
12、e displacements are generally to longer times(acceleration).3.3.5 stepped isothermal method(SIM)a method of expo-sure that uses temperature steps and dwell times to acceleratecreep response of a material being tested under load.3.3.6 mean test temperaturethe arithmetic average of alltemperature read
13、ings of the atmosphere surrounding the testspecimen for a particular temperature step,starting at a timenot later than established temperature ramp time,and finishingat a time just prior to the subsequent temperature reset.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthe
14、tics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Properties.Current edition approved July 1,2012.Published July 2012.DOI:10.1520/D7361-07R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book
15、 of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.3.7 offset modulus method or pointingdata analysismethod used to normalize any prestrai
16、n in the samples byshifting the origin of a stress vs.strain curve to an axis originof coordinates,that is,to coordinates(0,0).3.3.8 ramp and hold(R+H)testa creep test of very shortduration,for example,1001000 seconds.3.3.9 dwell timetime during which conditions(particularload)are held constant between temperature steps.3.3.10 compressive creep modulusin SIM analysis,theload divided by the percent compressive strain at any givenpoint in time.4.Summary of Test Method4.1 SIMA procedure whereby spe
