SOLUBLE SALT DAMAGE TO SPRAYED SEALS ON THE STUART HIGHWAY - PREVENTION AND MAINTENANCE

The problem of salt attack on bituminous sprayed seals is not new to the Department. Over the last 25 years, several roads, particularly on the Eyre Peninsula, have been affected to a greater or lesser extent. In 1971, RN 2200 Streaky Bay to Ceduna was constructed using mainly sea water and some saline bore water. The initial cutback primer was destroyed and a thin 10-15 mm layer on the top of the base course powdered. The problem was ascribed to the use of saline water for compaction. The damage was arrested with various degrees of success by application of a 16 mm seal, or repriming and sealing, and finally completely overcome by the replacement of primers by primerseals using SP- 1000. On the basis of this past experience, it was considered reasonable to use the same approach for the Stuart Highway. Unfortunately, due to extremely high soluble salt contents in construction materials, particularly in the compaction water (up to 24%), the application of the primerseal alone was inadequate. The sealed surface exhibited blistering, cracking, lifting at the edges and, in extreme cases, disintegration. Areas left for short periods as open surface, and subsequently sealed, also blistered, showing extensive white patches of salt on the surface. There was only limited information published on soluble salt damage to sprayed seals, with the exception of South African work which mainly applied to different local conditions and dissolved salts. This report describes the laboratory and field work carried out by the Department of Road Transport to prevent or minimise salt attack on sprayed seals.

  • Corporate Authors:

    South Australia Department of Transport

    P.O. Box 82
    Blair Athol, South Australia,   Australia 
  • Publication Date: 1992-5

Language

  • English

Media Info

  • Features: References;
  • Serial:
    • MTRD Report
    • Issue Number: 27
    • Publisher: TRANSPORT SA. MATERIALS TECHNOLOGY SECTION

Subject/Index Terms

Filing Info

  • Accession Number: 00629510
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ITRD, ATRI
  • Created Date: Jun 14 1993 12:00AM