Extended Hypolastic Model to Measure Geocell Pullout Behavior in Frozen Soil

This study develops an extended hypoplastic constitutive model to investigate the pullout behavior of geocell-reinforced ۱۳۱ Sand under freeze-thaw (FT) cycles, addressing the complex mechanical response of frozen soils in cold regions. By incorporating temperature-dependent parameters, intergranular strain effects, and ice formation mechanisms, the model captures nonlinear stress–strain behavior and thermal influences on soil–geocell interaction. Validated through drained triaxial compression tests at -۱۰°C and confining pressures of ۱۰۰ and ۲۰۰ kPa, the model accurately predicts stress–strain and volumetric responses. Numerical simulations in Plaxis ۳D reveal a ۷۸% increase in pullout resistance in frozen conditions (۲۱.۲ kN) compared to unfrozen conditions (۱۱.۹ kN) under ۲۰ kPa surcharge, attributed to enhanced ice bonding and interface shear strength. However, repeated FT cycles reduce pullout capacity by approximately ۱۵% after three cycles due to microstructural degradation and weakened confinement. These findings highlight the model’s robustness in simulating geocell performance under cyclic thermal loads, offering valuable insights for designing resilient geotechnical infrastructure in frost-susceptible environments.

کلیدواژه ها:

Geosynthetics ، Pullout ، Hypoplastic ، sand ، Finite element