Performance of Glass-Based Geosynthetic Reinforced RAP Bases for Unpaved Road Applications

The United States classifies over 1.3 million miles of its roadway network as unpaved and low-volume roads, which constitutes nearly 35% of the transportation infrastructure of the country. A significant portion of it consists of local and rural roads, which play a crucial role in connecting remote communities. Construction of these low-volume roads (LVRs) with Reclaimed Asphalt Pavement (RAP) base could potentially be a sustainable and cost-effective alternative to virgin aggregate base. However, the usage of RAP in pavement layers comes with several challenges such as reduced strength and stiffness, moisture susceptibility, and variable material properties. These drawbacks directly affect the pavement performance under repeated traffic loading, resulting in higher settlement and long-term deformations. In order to overcome the shortcomings and improve the performance of the pavements, the use of geosynthetics is a promising solution. The performance of conventional geosynthetics, such as geogrids and geotextiles is well-studied and proven to show significant improvement as reinforcing material. However, non-traditional geosynthetics, such as glass-based geosynthetics for base layer reinforcement, have been investigated minimally. Hence, this study explores using two different glass-based geosynthetics, GlasPave (GP) and GlasGrid (GG), as base layer reinforcement for RAP to improve the pavement performance. An experimental study was performed on unreinforced and reinforced sections with a 100% RAP base using large-scale cyclic plate load tests. From the test results, it was observed that the unreinforced section exhibited low stiffness and failed with a surface deformation of over 3 in. under 3,000 load cycles. Whereas the reinforced sections that were constructed with GP and GG installed at the mid-depth of RAP base layer showed significantly high stiffness and resulted in 50% to 75% less surface deformation when compared to the unreinforced RAP base section.