During 1969 to 1971, eight test pavements of open-graded asphalt friction courses were constructed in Pennsylvania. Details of design, construction, and performance of these pavements are discussed. Four test pavements incorporating two aggregate types and control sections of dense-graded bituminous surface were constructed in 1974 near Philadelphia. The asphalt friction courses were designed according to the Federal Highway Administration procedure modified in terms of asphalt mixing viscosities. The performance of the 1974 test pavements is evaluated every 6 months by obtaining skid test data at three speeds, by measuring air permeability, and by determining the average surface texture depths. Interim data obtained so far suggest that a minimum air void content of 25 percent is necessary to maintain the desired permeability that is lost in most pavements from traffic action and clogging by debris. A highly skid-resistant gravel aggregate was used for this project in the asphalt friction course and the dense-graded surface course. After 1 1/2 years' service, the skid-speed gradient of both pavements is almost equal and approaches 0.45. In the case of dolomite aggregate (medium skid resistance), the asphalt friction course has a substantially lower speed gradient compared to the dense-graded surface course. These tests are being continued to study long-range performance and durability. /Author/

Media Info

  • Media Type: Print
  • Features: Figures; Photos; References; Tables;
  • Pagination: pp 18-23
  • Monograph Title: Bituminous concrete materials, mixtures, and additives
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00185291
  • Record Type: Publication
  • ISBN: 0309026881
  • Files: TRIS, TRB
  • Created Date: Jan 13 1979 12:00AM