Temperature-dependent creep modeling of sands using a hyperbolic empirical equation

Understanding the temperature-dependent behavior of sands is essential for geotechnical engineering applications, especially in environments with long-term temperature variations. This study investigates the effects of temperature (T) on the shear strength and creep deformation (Δε_CP) of KMUTT and Hostun sands through a series of consolidated drained triaxial compression (CDTC) tests. Monotonic loading (ML) and sustained loading (SL) schemes were applied to evaluate shear strength and creep behavior under various stress levels (S_L) and temperatures. The temperature effect parameter (A^f) was introduced to quantify the reduction in shear strength at elevated T relative to a reference temperature (T₀ = 30°C. Experimental results show that shear strength decreases as temperature increases, with Hostun sand being more temperature-sensitive than KMUTT sand. Under SL, significant Δε_CP was observed, increasing with both S_L and T, while resumption of shearing after SL did not affect peak shear strength. A hyperbolic empirical equation was developed to predict Δε_CP for a given creep duration (Δt_CP), S_L, and T, incorporating temperature effects via A^f. The model was validated with experimental results and showed strong predictive capability, especially during the primary creep stage. However, discrepancies appeared at high S_L, where secondary creep effects became more pronounced. The proposed model offers a practical framework for predicting long-term creep deformation in sands under temperature variations, enhancing geotechnical design in thermally influenced environments.