Assessment of Advanced Hypoplastic Models for Simulating the Dynamic Response of Liquefiable Sloping Ground in LEAP Experiments

Abstract The present study conducts a systematic comparative assessment of advanced hypoplastic constitutive models for simulating the seismic response of liquefiable sloping ground. Three representative models are selected for evaluation, namely the hypoplastic model with intergranular strain (HP + IS), the hypoplastic model with intergranular strain anisotropy (HP + ISA) and hypoplastic model with fabric change effect and semifluidized state (HP + SF). The study determines the material parameters for each selected hypoplastic model based on previous Type B predictions and illustrates their characteristic constitutive behaviour through element test simulations. A total of eight dynamic centrifuge tests of mildly sloping submerged sand deposits are simulated from LEAP-UCD-2017 and LEAP-Asia-2019 with a wide range of initial relative densities and excitation intensities. The finite element (FE) models are created in ABAQUS with a coupled $$\mathbf{u}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>u</mml:mi> </mml:math> - $$p$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>p</mml:mi> </mml:math> formulation user-defined element. The comparative analysis, based on numerical predictions and experimental measurements, illustrates the capabilities and limitations of selected hypoplastic models in predicting different system response quantities, i.e., acceleration, excess pore water pressure, and surface lateral displacement. It also addresses the role of constitutive ingredients in the boundary value simulations. Generally, all the selected hypoplastic models capture the dynamic responses of acceleration and excess pore water pressure with reasonable success and the HP + SF model shows relatively improved performance in predicting lateral displacements when appropriate parameter calibration is employed.