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The increasing use of geosynthetics in reinforced systems is an important aspect that requires through understanding of their behavior and validation for the assumptions in their design. Geosynthetics are exposed to creep, which leads to time dependent strains and undergoes deformation of the structural systems. The creep behavior of two major types of synthetic polymers of geotextiles and geogrids, polyethyleneterephthalate (PET) and polypropylene (PP) are evaluated using accelerated test methods, Stepped Isothermal Method (SIM) and Stepped iso-Stress Method (SSM). SIM is an accelerated test method based on the principle of Time temperature superposition, using elevated temperature. SSM, a new accelerated technique similar to SIM but the acceleration is now obtained by increasing the stress in steps. SIM and SSM uses single specimen throughout a sequence of elevated temperature and stress. The application of these two methods is investigated. In this study, six different samples namely 1-GTX (Woven slit yarn geotextile fabric), 2-GTX (Nonwoven thermobonded geotextile fabric), 1-GGR (Warp-knitted geogrid with layer of nonwoven fabric), 2-GGR (Biaxial extruded geogrid, mesh size: 35?35), 3-GGR (Uniaxial extruded geogrid, mesh size: 42х42) and 4-GGR (Woven PVC coated geogrid, mesh size: 22х22) were tested using accelerated test methods- Stepped Isothermal method and Stepped iso-Stress Method. Tensile creep behavior of all the samples were evaluated and the predicted creep deformation for a period of 30 years has been analyze, and PET samples showed better resistance to creep than PP samples.