Synergistic influence of geogrid material and bio-inspired geometry on rutting performance

Abstract

Geogrids are widely used to mitigate rutting in pavements; however, most prior studies have examined the effects of geogrid geometry and material independently. Insights from natural systems, such as spider webs, suggest that these factors can interact synergistically to influence structural performance. This study investigates the combined influence of geogrid material properties and bio-inspired geometry on rutting performance by evaluating novel geogrids developed using a Bio-Inspired Design (BID) methodology. Prototypes of traditional triaxial and bio-inspired geogrids were fabricated via 3D printing using two materials with contrasting stiffness and extensibility: polypropylene and polylactic acid. Bench-scale rutting tests were conducted on two-layer laboratory pavement sections, with surface deformation monitored using linear variable displacement transducers (LVDTs) and 3D scanning. The results indicate that bio-inspired geometries are more sensitive to material selection than traditional triaxial geogrids. Material-sensitive geometries exhibited optimal performance when higher-performing materials were paired with appropriately designed geometrical layouts, demonstrating synergistic improvement in delaying rutting development. In contrast, for geometries exhibiting low material sensitivity, substituting higher-cost materials with lower-cost or more sustainable alternatives did not compromise rutting-mitigation performance. These findings highlight the importance of considering geogrid geometry and material properties together to achieve cost-effective and performance-optimized pavement reinforcement solutions.