Research Projects

The insufficient shear strength at the soil-reinforcement interface has been widely identified as a major cause of failure in reinforced soil structures. Traditional geogrids, commonly made of polyethylene or polyester, have dominated the market and are characterized by smooth surfaces and various aperture shapes. Over time, the aperture shapes of geogrids have evolved to improve interlocking capabilities, yet their surface characteristics have remained largely unchanged. This limits their ability to achieve optimal interlocking and interface friction with soil particles. Given that the performance improvements of geogrid-reinforced soil systems largely depend on the soil-geogrid interaction, enhancing these properties could lead to significant advancements in their application. This research proposes a novel solution in the form of a “Textured Geogrid (TG)” system. The TG system is designed with surface textures on the ribs of the geogrid and anchor pins at the junctions, which together create a synergistic improvement in shear resistance. The surface textures enhance interface resistance along the longitudinal ribs, while the anchor pins provide passive resistance along the transverse ribs. This dual mechanism is expected to significantly increase the pullout resistance, addressing a critical need for more robust reinforced-soil systems. The geometrical modifications proposed are highly material-efficient, requiring minimal additional resources while offering a substantial improvement in performance. The project involves designing and evaluating different textured geogrid configurations. The effectiveness of these configurations will be assessed through systematic pull-out testing, a proven experimental approach for quantifying the interaction between soil and geogrid surfaces. These tests aim to establish guidelines for implementing TGs in practical reinforced soil applications, with a particular focus on enhancing the stability of retaining walls. Further, a key innovation of this research lies in its manufacturing approach. Textured geogrids will be produced using additive manufacturing (3D printing) technology, employing Poly Lactic Acid (PLA), a bio-based filament. Unlike traditional extrusion processes, which are energy-intensive and reliant on fossil fuel-derived polymers, this method offers multiple sustainability benefits. PLA, being derived from renewable resources, reduces dependency on non-renewable materials. Additionally, additive manufacturing minimizes material waste, enables high customization, and significantly lowers the carbon footprint associated with geogrid production. This combination of performance enhancement and sustainability positions the textured geogrid as a transformative solution for reinforced-soil applications. The proposed research aims not only to improve the mechanical performance of geogrid-reinforced structures but also to contribute to environmentally sustainable practices in geosynthetic manufacturing.