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Research Reports

An Evaluation of Granular Overlays in Washington State--A Summary

Description: Granular overlays have been used by the Washington State Department of Transportation (WSDOT) for about 30 years. Since the mid-1980s and along with the full implementation of the WSDOT Pavement Management System (WSPMS), WSDOT has been interested in examining the performance of granular overlays. It is felt by WSDOT that the performance of this rehabilitation treatment is better than one might reasonably expect. Further, past practice in Washington State occasionally required that the preexisting surfacing (often several bituminous surface treatment (BST) layers) be scarified prior to placement of the crushed rock layer. This summary report overviews the study and conclusions.

  • Date Published: May, 1991
  • Publication Number: WA-RD 226.2
  • Last Modified: September 28, 2007
  • Authors: Daniel J. O'Neil, Joe P. Mahoney, Newton C. Jackson.
  • Originator: Washington State Transportation Center (TRAC)
  • # of Pages: 68 p., 1,423 KB (PDF)
  • Subject: Crushed rock, Elastic analysis, Evaluation, Granular materials, Guides to the literature, Literature reviews, Nondestructive tests, Overlays (Pavements), Pavement performance, Pavements, Service life, Stiffness.
  • Keywords: Granular overlay.
  • Related Publications: An Evaluation of Granular Overlays in Washington State: Final Technical Report, (WA-RD 226.1).


This abstract was last modified April 29, 2008