WHEN CRACKS START TO SHOW

This article gives some of the background to Concrete Society Report No. 44 on assessing risk of crack-induced corrosion of reinforcement in concrete. Three key factors seem to influence the risk of crack-induced corrosion: (1) service environment; (2) crack orientation with respect to the reinforcement; and (3) the nature of the steel and concrete reinforcement. For corrosion to occur, depassivating substances (usually carbon dioxide and chlorides), oxygen and moisture must be present in sufficient concentration around the reinforcement. The orientation of cracks with respect to embedded reinforcement significantly affects the risk of corrosion; distinction is made between the effects of coincident cracks, along the line of reinforcement, and intersecting cracks across it. The permeability and moisture content of uncracked concrete cover decisively influences the rate of chloride-induced corrosion. Reinforcement type also seems to influence the risk of crack-induced corrosion. A flow chart shows a procedure that could be used to assess the risk of crack-induced corrosion. In most cases, evaluation of whether corrosion is likely can be made by conducting a visual inspection of the structure and some routine concrete testing. Further tests can be applied if the results are inconclusive.

  • Availability:
  • Corporate Authors:

    THE CONCRETE SOCIETY

    112 WINDSOR ROAD
    SLOUGH, BERKSHIRE  United Kingdom  SL1 2JA
  • Authors:
    • ARYA, C
  • Publication Date: 1995

Language

  • English

Media Info

  • Features: References;
  • Pagination: p. 22-3
  • Serial:
    • CONCRETE
    • Volume: 29
    • Issue Number: 6
    • Publisher: THE CONCRETE SOCIETY
    • ISSN: 0010-5317

Subject/Index Terms

Filing Info

  • Accession Number: 00720778
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: May 24 1996 12:00AM