REPORT ON INVESTIGATIONS INTO METHODS OF LIMITING THE DAMAGE TO REFLECTION CRACKED PAVEMENTS CARRIED OUT ON EXPERIMENTAL SITES ON ROAD N4 (PRETORIA-BRONKHORSTSPRUIT) AND ROAD S12 (CLOVERDENE-ARGENT) FROM OCTOBER 1966 TO JULY 1971

Extensive transverse reflection cracking occurred on two roads in the Transvaal constructed with cement-treated bases and thin premix surfacings. In some cases, depending on the weight and intensity of the traffic, the cracking had developed into block cracking accompanied by pumping with a rapid deterioration in the structural condition. This was mainly caused by the ingress of water at the cracks in association with heavy wheel loads. The program of research was aimed at developing economical maintenance techniques by which damage to the pavement structure due to reflection cracking could be minimized. This report described the work that was done which included rolling with an impact roller, overlays of asphaltic concrete and gap-graded premix, double surface dressings, and various types of crack sealing. The object of impact rolling was to break down the size of the cement-treated blocks in order to decrease the magnitude of the thermal movements at the edges of the blocks. Up to 100 mm of gap-graded premix and up to 75 mm of asphaltic concrete were laid, and different binders were used with the double surface dressings. The experimental sections have been inspected at intervals and the report gives details of any cracking or pumping which occurred up to December 1972. Comparison of the condition of the treated road sections with adjacent untreated sections leads to the following iterim conclusion: it is important to prevent the ingress of water to the foundation layers with the type of construction used.

  • Availability:
  • Corporate Authors:

    South African Council for Scientific & Indus Res

    P.O. Box 395
    Pretoria, Transvaal,   South Africa 
  • Publication Date: 1973-9

Media Info

  • Pagination: p. 3
  • Serial:
    • VIA
    • Volume: JG14
    • Issue Number: 2
    • Publisher: VIA
    • ISSN: 1093-1716

Subject/Index Terms

Filing Info

  • Accession Number: 00262278
  • Record Type: Publication
  • Report/Paper Numbers: RC/3/73
  • Files: TRIS
  • Created Date: Oct 22 1974 12:00AM