Significance and Use
5.1 This test method is developed for use in the determination of anticipated total elongation or time to rupture that may occur in geosynthetics under sustained loading conditions.
5.2 This test method is not intended for routine acceptance testing of geosynthetics. This test method should be used to characterize geosynthetics intended for use in applications in which creep or creep rupture is of concern. The plane strain or rupture condition imposed during testing must be considered when using the test results for design.
5.3 The basic distinctions between this test method and other test methods for measuring tension creep and creep rupture behavior are (1) the width of the specimens (Section 8) and (2) the measurement of total elongation or time to rupture from the moment of specimen loading. The greater widths of the specimens specified in this test method minimize the contraction edge effect (necking) that occurs in many geosynthetic materials and provides a closer relationship to actual material behavior in plane strain tension conditions.
5.4 The creep or stress rupture of a given geosynthetic is likely to be reduced in soil because of load transfer to the soil. The unconfined environment represents a controlled test, in which the results are conservative with regard to the behavior of the material in service. Confined or in-soil testing may model the field behavior of the geosynthetic more accurately.
Scope
1.1 This test method is intended for use in determining the unconfined tension creep and creep rupture behavior of geosynthetics at constant temperature when subjected to a sustained tensile loading. This test method is applicable to all geosynthetics.
1.2 The test method measures total elongation of the geosynthetic test specimen, from the time of loading, while being maintained at a constant temperature. It includes procedures for measuring the tension creep and creep rupture behavior at constant temperature of conditioned geosynthetics as well as directions for calculating tension creep and creep rupture curves.
