This paper presents a multiscale analysis of the mechanical behavior of polyvinyl chloride (PVC) geomembranes under uniaxial tensile loading using a 3D Discrete Element Method (DEM)-based model that incorporates microstructural characteristics. This study captures the relationship between mesoscopic deformation mechanisms and macroscopic responses by examining failure points, internal force distribution maps, and structural configuration evolutions. The macroscopic stress–strain responses predicted by the numerical model are qualitatively compared with experimental data. The results unveil insights into the elementary mechanisms responsible for macroscopic behavior. Additionally, the investigation is further extended to assess the effects of key microstructural features on the mechanical response of PVC GMs, specifically tensile performance. Special emphasis is placed on the effect of plasticizer content and polymerization degree (that is chain’s length). The results highlight the significant influence of microstructural parameters on the stress–strain response, failure evolution, and internal force distributions. The findings demonstrate that the plasticizer enhances flexibility by improving stress redistribution and delaying crystallite fragmentation, while longer chains provide uniform stress fields, affecting elasticity and flexibility, and delaying micro-mechanical failure. These findings demonstrate how molecular-level modifications, whether from formulation changes or ageing, can optimize the macroscopic behavior of PVC material, especially PVC GMs for engineering applications.
Akel et al. (Fri,) studied this question.