Full-Depth Reclamation: Cost-Effective Rehabilitation Strategy for Low-Volume Roads

Abstract

Full-depth reclamation with or without various stabilizers has been successfully used as a rehabilitation strategy in California since 2001. Long-term field monitoring on a number of full-depth reclamation projects that use foamed asphalt with portland cement as the stabilizer combined with a comprehensive laboratory study resulted in the preparation of guidelines and specification language for this rehabilitation strategy in 2008. However, the design criteria were essentially empirical in line with California design procedures for this level of rehabilitation project. There has been growing interest in the use of full-depth reclamation with no stabilizer as a rehabilitation option for lower-volume roads and in the use of mechanistic design in a greater range of rehabilitation projects. Consequently, the research initiative was extended to a second phase to include accelerated load testing on an instrumented test track constructed with four full-depth reclamation strategies to gather data for the development of performance models that can be included in mechanistic–empirical rehabilitation design procedures. This paper summarizes the results of a set of tests in this accelerated loading study, which compared dry and wet performance of a pavement rehabilitated with full-depth reclamation without any stabilizer. The section performed well in terms of expected low-volume traffic (i.e., up to 500,000 equivalent single-axle wheel loads). Poorer performance under wet base course conditions emphasized the need for appropriate drainage on low-volume road structures. The findings indicate that full-depth reclamation with no stabilizer, followed by the placement of an appropriate surface treatment or thin asphalt concrete layer, is a potentially cost-effective rehabilitation strategy for distressed low-volume pavements.