Open-Graded Asphalt Mixes: Hydraulic Permeability and Mechanical Characteristics

Skid and hydroplaning induced by water film on pavements are critical problems for road safety. Porous pavements are considered to be potentially effective solutions. A new low cost, user friendly piece of equipment for measurement of Darcy's hydraulic permeability of pavement is presented. The reliability and repeatability of measurements have been verified. Additionally, the experimental outcomes of a research project are discussed, in order to assess the correlation between the hydraulic permeability of pavement and bitumen content, voids percentage, and aggregate grading. Very cautious standards for mix designs are imposed in order to have adequate permeability and are validated after pavement construction. The final permeability obtained with respect to those standards is always higher than the needed value. It affects relevant economic and environmental costs. After verifying in the laboratory the hydraulic permeability and the mechanical resistances of the 24 pavement samples, the effectiveness of an experimental procedure for the optimization of the mix design in terms of hydraulic and mechanical standards is assessed. The experimental results show that permeability always decreases if Young's modulus of the asphalt pavement layer increases. Aggregate grading influences this relationship and the procedure of making samples influences the final mechanical and hydraulic properties. Relevant economic and environmental benefits are a reasonable expectation.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 63-74
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01126311
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 13 2009 2:58PM