Micro-CT–based pore network modeling for hydraulic conductivity prediction of needle-punched nonwoven geotextiles

Abstract

Accurate prediction of hydraulic conductivity in needle-punched nonwoven geotextiles is still difficult due to their complex, heterogeneous fibrous microstructure. Traditional empirical models often fail to capture the intrinsic link between 3D pore architecture and macroscopic flow behavior. This study presents an image-based pore network modeling approach that directly bridges real microstructure and hydraulic performance. High-resolution X-ray micro-computed tomography (micro-CT) was used to reconstruct the 3D internal geometry of a commercial geotextile. A physically representative pore-throat network was extracted, preserving actual connectivity and throat-size distribution. Hydraulic conductivity was then simulated by solving the Stokes equations on this network under Darcy flow conditions. This work demonstrates that incorporating realistic microstructural data into pore-scale models significantly enhances predictive accuracy and provides new insights into flow mechanisms in fibrous porous media. The proposed framework offers a promising digital tool for virtual design and performance evaluation of geosynthetics, reducing reliance on costly and time-consuming physical trials.