Resilient response of geosynthetics from cyclic and sustained in-air tensile loading

摘要

Resilient response of geosynthetics is defined as the tensile stress-strain or load-strain response of the material after the application of many cycles of similar load and is used in the analysis of applications involving repetitive loads, such as highway pavements reinforced with geosynthetics. Cyclic loads experienced by geosynthetics in reinforced roadways produce both creep and stress relaxation. Current test standards use a load form corresponding to cyclic stress relaxation. This test standard does not address whether a simpler load form involving non-cyclic, monotonic sustained loads producing load relaxation or creep produces comparable values of resilient modulus. A series of wide-width uniaxial tensile tests were performed on a biaxial geogrid and a woven geotextile. Various load forms were employed involving cyclic and sustained loading, and loading producing load relaxation and creep. Resilient modulus at the end of each type of loading was measured and compared. The results show modest differences in resilient modulus between the different load forms examined and supports the development of a commercial test standard using the simplest type of load form available, which is sustained stress relaxation for displacement-controlled test frames and sustained creep for load-controlled test frames.