Effects of cyclic temperature change on the creep behavior of Hostun sand

Geotechnical engineering materials, both in-situ and backfill materials such as gravel and sand, must support loads from civil engineering structures like buildings, bridges, and retaining walls, which can be assumed to apply constant stress. When subjected to constant loads, these materials undergo deformation known as "creep," a long-term behavior crucial for structural service life. Besides constant loading, geotechnical materials also experience environmental temperature changes, such as soil temperature variations with atmospheric conditions. Previous research has shown that temperature differences affect sand’s shear strength, elastic modulus, and creep behavior. However, the influence of cyclic temperature changes on creep behavior has not been studied. This research investigates the influence of cyclic temperature changes on the creep behavior of Hostun sand through temperature-controlled triaxial compression tests, shearing samples to various stress ratios after which they are kept constant, while simulating cyclic temperature variations between 30 and 60 degrees Celsius. The results show that the creep strain mobilized together with cyclic temperature changes does not influence the shear strength of Hostun sand. Nevertheless, cyclic temperature changes significantly increase the creep strain, resulting in higher values compared to that under constant temperature conditions. Additionally, as the stress ratio increases, the difference in creep strain between the maximum and minimum temperature points during cyclic temperature changes decreases.