Title: Durability of Concrete in Marine Environment--A Review

Author(s): P. Kumar Mehta

Publication: Symposium Paper

Volume: 65

Issue:

Appears on pages(s): 1-20

Keywords: admixtures; cathodic protection; climate; concrete durabilty; corrosion; cracking (fracturing); deterioration; harbor structures; hydration; marine atmospheres; mix proprotioning; permeability; portland cements; reinforcing steels; sea water.

DOI: 10.14359/6343

Date: 8/1/1980

Abstract:
Case histories of deteriorated Portland-cement concretes exposed to sea water, both in mild and cold climates, show that permeability is the most important characteristic determining the durability of concrete. Whether due to improper mix proportions, or poor concreting practice, or cracking of concrete, permeable concretes tend to deteriorate in marine environment. This is because the hydration products of portland cement are chemically unstable to certain aggressive components present in sea water. In this paper, the chemical reactions between the aggressive components of sea water and the constituents of hydrated portland cement are reviewed. The physical processes of deterioration associated with these chemical reactions are discussed. Also discussed are the fundamental anodic and cathodic reactions involving corrosion of reinforcing steel in concrete exposed to sea water. A summary of recent work on the effectiveness of various admixtures in reducing the permeability of hydrated portland cement is given.