Empirical Design Methods for Geosynthetic-Reinforced Low-Volume Roads

Abstract

Low-volume road managers are forced to focus their limited resources on higher-capacity infrastructure, with minimal funding for repairing, maintaining, or improving unpaved low-volume roads as a result. Insufficient funding requires road managers to consider the use of innovative stabilization and reinforcement materials to reduce operational costs and minimize maintenance requirements. Geosynthetic materials have been used for many years to improve the quality of low-volume roads in an effort to reduce the amount of aggregate required or to extend the service life of the pavement. The objective of this paper is to review the use of geotextiles and geogrids in unpaved roads, compare common design approaches, discuss advantages and limitations of current design methods, and seek directions for future research efforts to improve the implementation of geosynthetic technologies. This paper summarizes prior research activities to establish the historical performance of geosynthetic-reinforced unpaved roads. Once the performance benefits have been generally supported, current design methods for separation and reinforcement, including advantages and limiting assumptions, are discussed. The sensitivity of the design methods to specific input parameters is examined to provide users with an understanding of the impact of design assumptions on the resulting structural design. Design methods are compared by performing designs with different methods for a variety of site conditions. Finally, the paper discusses the essential requirements for the development of more advanced design methods.