This paper describes the results from an investigation carried out at Plymouth polytechnic and sponsored by the transport and Road Research Laboratory (TRRL) to define the mechanisms by which reflection cracks occur in bituminous surfacings overlaying cement bound roadbases. Three mechanisms of reflection cracking have been identified and modelled: tensile yield of the wearing course which will induce crack propagation downwards from the surface; tensile fatigue of the underside of the bituminous layer which will cause fracture and crack propagation upwards to the surface; and shear fatigue, which will accelerate crack growth initiated by one of the thermally controlled mechanisms. The models developed predict that the tensile yield mechanism is the more important as it will affect all roads with lean concrete roadbases. The paper also characterizes bituminous mixes in terms of their susceptibility to reflection cracking and suggests modifications to conventional mix design which may be adopted to inhibit crack growth. Although the results are based on an analytical and laboratory study they are consistent with field observations recorded as part of the research programme.

  • Availability:
  • Corporate Authors:

    Thomas Telford Limited

    London,   United Kingdom 
  • Authors:
    • Foulkes, M D
  • Publication Date: 1989-10


  • English

Media Info

  • Pagination: p. 289-97
  • Serial:
    • Volume: 6
    • Issue Number: 5
    • Publisher: Thomas Telford Limited
    • ISSN: 0263-788X

Subject/Index Terms

Filing Info

  • Accession Number: 00497985
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS, ATRI
  • Created Date: Sep 30 1990 12:00AM