Geosynthetics in dams and water reservoirs under slope instability conditions: state of the art and challenges in geotechnical engineering

Geosynthetics are polymer-based materials widely applied in dams and water reservoirs to enhance impermeability, structural stability, and overall sustainability. Studies have focused on the use of geosynthetics for erosion control, seepage/stabilisation, and geoenvironmental linings. However, a gap remains in the systematic review linking the performance of geosynthetic barriers to slope stability assessment under specific dam failure scenarios, such as rapid water-level drop, transient seepage, liquefaction, and seismic loading. This study aims to analyze the scientific literature on applications of geosynthetic systems and their performance in dams or natural/artificial water reservoirs documented in Scopus and Web of Science using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method and bibliometric analysis. Variables including geosynthetic type, configuration, selection criteria, application context, and mechanical performance under seepage and slope stability conditions were evaluated. The study identified that more than 30% of cases employ single-layer geomembranes (High-Density Polyethylene, Polyvinyl Chloride) due to their high impermeability, mechanical strength, and cost-effectiveness in regions where impermeable clay is unavailable. Multicomponent configurations tend to present high sustainability categories, especially when vegetated elements (Vetiveria zizanioides) or biodegradable materials are included. The applied numerical models focus on the analysis of leaks and seals with Geosynthetic Clay Liner, which has received sustained interest to date. Future research directions focus on pilot projects for modular renovation, continuous monitoring using remote sensing techniques, medium-term (5–10 years) testing of geosynthetic degradation, and the development of hybrid materials (recycled polymers with natural fibres). Compared with conventional solutions, geosynthetic systems represent a new generation of climate-adaptive infrastructure, offering environmental, economic, and social benefits.