Improved Life for Longitudinal Joints in Asphalt Pavement

Longitudinal joints in asphalt pavements have drawn a significant amount of research attention in the last 20 years. It seems to be generally accepted that low density at the joint is the culprit in longitudinal joint failures. Unless they are properly sealed and compacted, longitudinal joints prove too permeable to resist damage that shortens the effective life of the joint. Research suggests that the problem is the same for overlay joints and new pavement joints. Poor density generally results from the construction process, in which crews must lay multiple lanes of hot-mix asphalt (HMA). Because crews lay one lane at a time, one mat will be paved hot against another that is cold, and this differential at the joint makes proper compaction challenging. The most widely accepted design of longitudinal joints for optimal performance is the Michigan or notched-wedge joint employed by the Wisconsin Department of Transportation (WisDOT). This has been a standard since research in the late 1990s by the National Center for Asphalt Technology. Nevertheless, longitudinal joint performance continues to be the subject of research attention, construction guidelines, and pilot projects of construction methods, designs and products. States and national agencies have taken several approaches to this problem. This report first looks at the current WisDOT approach to establish a baseline. It then reviews research and guidelines regarding joint design, and then looks at research devoted to proper compaction and density of HMA at the joint. Following this section it considers construction and specifications, including documents that detail best construction approaches and that look at the development of a joint density specification to ensure proper construction. This report also looks at recommendations and research from a few states on the use of sealants to prevent or mitigate joint failure, and reviews the use of a field permeameter for quality control. Finally, it reviews the research in progress that five agencies are conducting on these topics.


  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01100214
  • Record Type: Publication
  • Created Date: May 27 2008 8:18AM