Retreading machines, allowing a thinner than usual replacement wearing course to be used, and repaving machines which remove old asphalt, mix it with new material and relay it, are beginning to be accepted by local authorities. Two machines, the Purser/Jackson Retreader, and the Colas Repaver, both of American design, have been tried in this country with varying success. The Colas machine scarifies the old surface to the depth of 20 mm mixing the loosened material with an equal quantity of new material and lays a new depth of some 40 mm. For inlay work some 20 mm must be removed first. The Purser/Jackson system heats up the top 20 mm of surface to about 115 deg C and an oscillating tamping screen then agitates and reshapes the surface before a conventional paver lays some 25 mm of new material. A static asphalt recycling plant has also been used by a Dutch contractor, Stevin, to reprocess old asphalt consisting of a mixture of surfacing and base. The material is not suitable for wearing surfaces but has been successfully used as a base. The old asphalt is not heated directly to avoid oxidation, and is mixed with a softening agent to restore its original properties before laying. /TRRL/

Media Info

  • Features: Photos;
  • Pagination: p. 18-19
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00178629
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Sep 27 1978 12:00AM