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Research Report 390 The waterproofness of first-coat chipseal

Published: | Category: Integrated land use and transport systems , Research programme , Research & reports | Audience: General

This research project, undertaken in 2006 to 2008, confirms that traffic can force water through first-coat chipseal surfacings that do not visually show signs of cracking.

The research measured the change in moisture content after rain on a number of newly sealed sites. Although this testing showed a statistically significant increase in moisture over all sites, the increase was not dramatic.

The research concludes that water ingress can occur where a water film collects on the pavement. The film of water can occur either through rutting of the pavements, or if the crossfall and longitudinal shape is such that a sheet of water forms above the surface texture of the pavement.

Keywords: chipseal, moisture, New Zealand, pavement failure, potholes, rutting, waterproofing

Publication details

  • Author:
  • Published: September 2009
  • Reference: 390
  • ISBN/ISSN: ISBN 978-0-478-35240-5 (electronic) ISBN 978-0-478-35241-2 (print) ISSN 1173-3764 (electronic)) ISSN 1173-3756 (print))