VALIDATION OF 3D SEISMIC ANALYSIS FOR A SOIL-PILESUPERSTRUCTURE SYSTEM USING ADVANCED SOIL CONSTITUTIVE MODELS

The simulation of the seismic response of liquefiable soils requires con-stitutive models that accurately incorporate undrained behavior in their formulations. This paper evaluates the seismic predictive capabilities of three advanced constitutive models: one based on boundary surface elasto-plasticity and two on hypoplasticity. In this context, we employ an improved hypoplastic model for undrained monotonic loading (Liao et al., 2024) combined with the intergranular strain concept (Niemunis and Herle, 1997). The modified hypoplastic model, which accounts for the hardening rate, addresses some shortcomings of the hypoplastic refer-ence model (von Wolffersdorff, 1996), improving its performance under seismic loading. To assess the practical applicability of these advanced constitutive models, a 3D finite element simulation of a soil-pile-superstructure system was conducted in ABAQUS. This system was modeled as a case study to validate the advanced models using centrifu-ge test data. The results show that the modifications to the hypoplastic model rectify its predictive capabilities in seismic analysis, leading to im-proved predictions of pore water pressure accumulation and a more accurate representation of the bending moment response in the embed-ded pile.