Using Existing Pavement in Place and Achieving Long Life
The goal of this project was to develop reliable procedures and guidelines for identifying when existing pavements can be used in place and the methods necessary to incorporate the original material into the new pavement structure while achieving long life. “Long life” was defined as 50 years or longer from the time the pavement was renewed or rehabilitated until the next major rehabilitation. (This report does not provide guidance on the use of routine overlays designed for maintenance and preservation, which is included in the report and guide for SHRP 2 Renewal Project R26, Preservation Approaches for High-Traffic-Volume Roadways.)
The report and guide encourage longer-lasting renewed pavement designs; provide realistic, easy-to-use pavement thickness scoping assessments; and guide users through the data gathering process needed for input into designing and constructing a long-life pavement by using the existing pavement structure. The guide includes the following: project assessment manual; best practices for rehabilitation of flexible pavements and rigid pavements; guide specifications; life-cycle cost analysis; and emerging pavement technology. All the guidance has been incorporated into the web-based pavement design scoping tool, which is meant to complement, not replace, a transportation agency’s normal processes for design and pavement-type selection. The guide and web tool were developed with the support of several transportation agencies, including the Illinois Tollway Authority, Michigan DOT, Minnesota DOT, Missouri DOT, Texas DOT, Virginia DOT, and Washington DOT.
As a result of outreach to transportation agencies, a set of enhancements is currently under way and will be included as a future addendum to the report and guide. Those enhancements will include providing guidance on pavement thickness for 30 to 50 years of rehabilitated design life and updating the guidance and design table to incorporate precast concrete pavements and composite pavement as options for the rehabilitation strategy.
Authors: Newton Jackson, Jason Puccinelli, and Joe Mahoney