Suitable design approaches for interfaces involving geosynthetics under various loading and flow conditions.

This work integrates the research results conducted over several years, focusing on the behaviour of interfaces in applications involving geosynthetics. It addresses the importance of accurately characterizing the interfaces of geosynthetic-reinforced soil walls and steep slopes, landfill cover systems, and drainage systems to ensure their performance under both ultimate and serviceability limit states. For geosynthetic-reinforced soil walls and steep slopes, the research emphasizes the proper characterization of soil-geosynthetic interfaces under static and cyclic loading conditions, both in the short- and long-term. It provides essential guidelines for selecting design parameters for these structures, ensuring their stability under various loading scenarios. In landfill cover systems, the study investigates the behaviour of interfaces between different geosynthetics under static and seismic loading conditions, with special attention to potential damage arising from improper installation. The lecture offers a comprehensive approach to understanding these interactions and their impact on the longterm performance of landfill systems. Lastly, the research examines the soil/geotextile filter interfaces in drainage systems, particularly in contact with unstable cohesionless soils under different boundary conditions. It challenges conventional design methods and introduces a new methodology to design filter transitions in contact with internally unstable soils. These findings significantly contribute to designing and optimising geosynthetic applications in civil engineering, advancing theoretical understanding and practical implementation.