Reclaimed Stabilized Base – Stabilizing Agent Selection & Design

Reclaimed stabilized base (RSB) is a common technique utilized to rehabilitate roadways (e.g. NCHRP 144 Report, 2009; NCHRP 421 report, 2011). RSB involves reclaiming the base material and adding a stabilizing agent (e.g. cement, lime, calcium chloride, emulsion, foamed asphalt) to increase the strength and durability of the subbase structure. In this project, the research team plans to investigate the suitability of the various stabilizing agents for common subbase materials encountered in Vermont roadways and develop a process for VTrans to determine the applicability of RSB for a project, and the appropriate types and percentages of stabilizing agents. The team plans to investigate the performance of the stabilized sub-base materials in winter conditions, including ice lens formation and stiffness as well as long-term (multiple-year equivalents) freeze-thaw implication for durability through accelerated cold room testing. The outcomes of this research will assist VTrans in the scoping phase of the projects to determine applicability of RSB, and in the design and construction phases with guidance on appropriate stabilizing agents, and installation parameters, respectively.