In tests on roads with only bituminous macadam in the upper pavement structure, the main point of interest is the required thickness of the upper structure. Material requirements, frost resistance and economic aspects are also investigated. A test road constructed in 1974 was divided into ten sections of varying compositions and thicknesses. Lime stabilisation of the formation was found best. The most advantageous plant for spreading bituminous macadam directly on the formation is the grader; if lorries and a spreader are used, the formation is often churned up badly. The thickness of the upper structure depends on subsoil strength and choice of plant. If the formation is even and reasonably strong, a 25 cm layer can be placed by a spreader, while if the strength is low and/or variable, the upper structure must be placed in 2-3 layers. If a grader is used, then the first layer must be the thickest possible, the next layer being placed with a spreader so as to even out irregularities. Although a conventional upper structure of crushed rock + bituminous macadam is about skr. 8 cheaper per square metre finished road, excavation is reduced, construction is faster and total road width is smaller. Particularly in urban areas, all-bituminous construction is therefore more economical. /TRRL/

  • Corporate Authors:

    Svenska Byggnadsenreprenoerfoereningen

    P.O. Box 27029
    Stockholm 27,   Sweden 
  • Authors:
    • Lindhal, T
    • Lindah, E
  • Publication Date: 1975


  • Swedish

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: 92 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00133711
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Report/Paper Numbers: 13
  • Files: ITRD, TRIS
  • Created Date: Sep 4 1976 12:00AM