Stabilized HEPM for large-deformation hydro-mechanics in saturated porous media

Abstract

The accurate prediction of hydro-mechanical interactions in saturated soils is essential for assessing the stability of critical geotechnical infrastructure. However, modeling the coupled hydro-mechanical response of saturated soils involving large deformations presents a significant computational challenge, primarily due to the limitations of traditional grid-based methods in handling severe mesh distortion. The core of the proposed HEPM lies in its dual spatial discretization, which decouples the material motion from the numerical mesh. The physical continuum is discretized by a collection of particles that store all state variables, along with an auxiliary mesh used to construct the particle interpolation. Formulated within an Updated Lagrangian (UL) framework based on Biot’s theory, the method incorporates a particle-based Finite Increment Calculus (FIC) stabilization technique. This ensures the suppression of spurious pressure oscillations, thereby enabling the use of efficient equal-order interpolations for both solid displacement and pore pressure. The accuracy and robustness of the proposed method are validated through a series of benchmark tests, showing excellent agreement with analytical solutions for consolidation problems and highlighting its versatility in handling complex material nonlinearities, including nonlinear hydraulic behaviors. Ultimately, the results demonstrate the capability of the proposed framework to reliably solve complex failure problems in computational geomechanics, offering a robust numerical strategy that effectively overcomes mesh distortion and numerical instability in large-deformation hydro-mechanical analysis. Graphical abstract: [Figure not available: see fulltext.]