Using geosynthetics in flexible airport pavements

摘要

In recent years, there has been an increasing interest to improve pavement structures through mechanical stabilization by incorporating geosynthetic products within the structure. The Geosynthetic Materials Association (GMA) has identified eight categories of commercially available geosynthetics: geotextiles, geogrids, geonets, geocomposites, geosynthetic interlayers, geocells, erosion control materials and geomembranes. These materials serve multiple functions, including separation, filtration, drainage, reinforcement/stabilization, cushion/protection, confinement, stress relief, erosion protection and moisture barrier (Berg et al. 2000). Geotextiles and geogrids are the two most commonly used categories of geosynthetics for the purpose of reinforcement/stabilization. There have been numerous studies supporting the benefits of reinforcement/stabilization with the use of geotextiles and geogrids within a pavement structure attributed to the three mechanisms of (1) lateral restraint, (2) increased bearing capacity and (3) tensile membrane support. These primarily benefit the pavement structure by extending pavement life, reducing structural thickness or increasing rutting resistance. Studies document the benefits of how geosynthetic products can be an efficient way to improve the strength properties of materials used in pavement structures (Abu-Farsakh et al. 2016, Holtz et al. 1998, Perkins et al. 2005, Zornberg 2011). However, the majority of the studies focus on thinner highway pavement structures simulating vehicular traffic loading. Therefore, the U.S. Army Engineer and Research Development Center (ERDC), in collaboration with the Federal Aviation Administration (FAA), performed a laboratory cyclic plate load test study to collect data and verify the benefit of geosynthetic products on thicker airport pavement under simulated aircraft loading (Figure 1).