Long lasting durable mix as alternative of porous asphalt

A hybrid type of mix, which is composed of rough macro texture for road surfaces similar to that of porous asphalt, as well as the same waterproof level as that of stone mastic asphalt (SMA) for inside was developed at the Nippon Expressway Company Research Institute (NEXCO RI). For the two opposing functions in the concept, aggregate gradations of the hybrid mix were examined with a combination of the porous gradation for the stone part and SMA gradation for the sand part. By subjecting many roller-compacted specimens to laboratory tests, a prototype hybrid mix was finally obtained under a very limited aggregate gradation range with specific mix properties. A full-scale durability test showed that even after a steel plowing vehicle moving 200 times on the surface, the hybrid survived with almost no damage while the porous asphalt was much damaged. In order to solve bitumen’s run-off problems found in several projects, the prototype mix was reviewed for achieving less compaction energy by reducing the compaction blow times from 75 to 50 times. Finally a newly obtained mix enabled easier construction with sufficient texture and impermeability. This hybrid, one finishing mix with two functions, is expected to provide sufficient safety and long lasting durability as an alternative to porous asphalt.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: 15p
  • Monograph Title: 24th World Road Congress Proceedings: Roads for a Better Life: Mobility, Sustainability and Development

Subject/Index Terms

Filing Info

  • Accession Number: 01519950
  • Record Type: Publication
  • ISBN: 2840602679
  • Files: TRIS
  • Created Date: Mar 15 2014 3:38PM