Effects of hydro-mechanical material parameters on the capillary barrier of reinforced embankments

Abstract

This paper presents a numerical analysis of the water infiltration process in embankments reinforced with permeable geosynthetics. An emphasis is given to the study of the capillary barrier permanence at the soil-geotextile interface. For the analysis, an infiltration-deformation coupled model is used, and the numerical results are validated with experimental data. The proposed model properly describes the main characteristics of the capillary barrier phenomenon observed experimentally. A parametric analysis is performed to investigate the effects of the initial void ratio (e0), overconsolidation ratio (OCR), initial shear elastic modulus (G0), coefficient of compressibility (λ), anisotropy of the hydraulic conductivity (kr), initial suction (ψi), and water retention curve parameters (α and n′) on the performance of the capillary barrier during a rain infiltration process. Finally, a statistical analysis is carried out to evaluate the parameters that have influence on the development of pore water pressure (PW). The implemented infiltration-deformation coupled model shows the effect of the hydraulic parameters on the development of the capillary barrier -as commonly considered in conventional analysis- as well as the effect of the mechanical parameters of the soil and geotextile. The overall results highlighted the capability of the model, in combination with statistical analyses, to capture the complexity of the capillary barrier development in reinforced soil structures.