Institute for Transportation

About the research

The goal of this project is to quantify potential performance improvements for granular-surfaced (“gravel”) roads constructed with an embedded layer of woven or non-woven geotextile, with and without beneficiated fly ash (BFA) blended into the granular surface course. To enhance sustainability and control material costs, the granular surface course will consist of 30% fresh Class A roadstone and 70% recycled asphalt pavement (RAP). The roadway performance will be quantified by laboratory tests as well as in situ testing and sampling of field test sections through two seasonal freeze–thaw periods. The field performance will be assessed through measurement of particle breakage from particle size distribution (PSD) curves sampled over time, in situ stiffness and strength profiles, resilient modulus and plastic strain from repeated load cyclic triaxial tests, and field observations of surface distress such as rutting and potholes. The overall workplan includes construction of field test sections, performance of in situ tests and sampling through two winter-spring seasons, and laboratory investigations to quantify both the short-term and long-term benefits of woven and non-woven geotextiles with and without BFA, to help develop construction guidelines and specifications.