Document Archives

The Durability of Steel Embedded in Lightweight Concrete

• ID:

  935

• ESCSI:

  4350.004

• Author:

  Grimer

• Publication Name:

  BRS Symposium on Lightweight Concrete

• Type of Publication:

  Paper

• Publisher:

  Building Research Station (BRS)

• Dated:

  1965

• Issue/Volume:

  Circa 1965 or 1966

• Other ID:

• Page(s):

  7 pages

• Reference List:

  Y

• Abstract:

  The degree of protection afforded to reinforcement by the cover was studied with concretes made with five lightweight aggregates and one dense aggregate by exposing 150 specimens outdoors in a highly polluted atmosphere. The variables were the type of aggregate (three lightweight and one gravel), the mix proportions (1:5 and 1:9 by volume), the thickness of the cover (1 in. to 2 in.) and the length of exposure (one to six years). After six years’ exposure no appreciable corrosion was observed in 1:5 lightweight concretes or in gravel concretes. Corrosion of the bars with 1-in. (2-5 cm) cover occurred in 1:9 lightweight concretes and caused cracking of some specimens. Corrosion of the steel was associated with carbonation of the concrete in contact with it. The main factor affecting the depth of carbonation was the mix, the type of aggregate having relatively little effect. A well-defined relationship was found to exist between depth of carbonation, cement content and alcohol absorption.