Prediction of Compressive Creep Behavior of Three-Dimensional Geomat Using Stepped Isothermal Method

In this work, compressive creep behavior of 3D geomat is studied. Generally, the creep tests methods include conventional creep test and accelerated methods allow activating the deformation processes by temperature, e.g., a stepped isothermal method (SIM). Laboratory tests showed that accelerated creep tests significantly affect the predicted creep deformation of geomat. Compressive creep testing of polypropylene geomat was considered to estimate the effect of thickness in accelerated testing. When testing a geomat in a compressive creep test, it was shown that the results of accelerated temperature prediction do not accurately reflect the nature of deformation of such materials. At low loads, the deformation increases sharply owing to the deformability of the 3D structure, which does not correspond to the conventional creep test measurements. At large deformations, the curve should reach a plateau due to the increasing rigidity of the material and sharply decreasing thickness. It can be concluded that the predicted curves do not plausibly reflect the nature of the deformation of such materials. The results of this study only applies to the conditions of the present research, and so further tests are needed with 3D geomats to support the research.