Numerical modeling of liquefiable slopes using Hypoplasticity with ISA and semifluidized states: Benchmarking against LEAP centrifuge data

This study analyzes numerical simulations of a water-saturated, liquefiable sandy slope centrifuge test subjected to dynamic base excitation. The benchmark centrifuge experiment was executed within the scope of the LEAP-2017 project by Carey et al., (2020) . Numerical simulations were conducted in PLAXIS, a finite element modeling software, with the soil’s mechanical behavior modeled through a recently developed hypoplastic model for sands, accounting for semifluidized states and fabric change effects, as proposed by Tafili et al., 2024. The constitutive model was carefully calibrated using element tests performed with Ottawa F-65 sand, which was also employed in the centrifuge test. The dataset comprised oedometric compression tests, drained and undrained monotonic triaxial tests, and undrained cyclic triaxial tests, considering different initial densities and effective stresses. A comparison of measured and predicted results revealed reasonable agreement in terms of acceleration time history, spectral response, and the evolution of excess pore water pressure. These findings provide a comprehensive assessment of the predictive capabilities and limitations of the constitutive model in forecasting the behavior of geotechnical structures under earthquake loading.