Multiphysics analysis of tramway geotechnical infrastructure: numerical modeling

Under realistic field conditions, geotechnical infrastructures are usually influenced by complex interactions of mechanical behavior under the action of an internal water flow. This mechanism could be the main origin of damage to embankments. This study develops a new hydromechanical approach based on Darcy's law model and Biot's poroelastic concept to investigate the behavior of soil with and without Geotextile under realistic conditions. The problem's numerical solution is carried out using a finite element method. The proposed 2D model was implemented in COMSOL Multiphysics Software. Under coupled hydro-mechanical behavior, the stress in porous materials causes a volumetric change in strain, which causes fluid diffusion. Consequently, pore pressure dissipates through the pores. To discuss the advantages of coupled hydro-mechanical modeling and evaluate the Geotextile performance, volumetric strain, pore water pressure, storage, and displacement are compared for a mechanical, hydraulic, and hydromechanical model. These analyses were undertaken in connection with a tramway embankment project in a marshy area in Sidi Bel Abbes. The simulation results show better results for Geotextile and embankment in hydro-mechanical coupled modeling.