The corrosion of steel reinforcement bars in reinforced concrete structures exposed to severe marine environments usually is attributed to the aggressive nature of chloride ions. In some cases in practice corrosion has been observed to commence already within a few years of exposure even with considerable concrete cover to the reinforcement and apparently high quality concretes. However, there are a number of other cases in practice for which corrosion initiation took much longer, even in cases with quite modest concrete cover and modest concrete quality. Many of these structures show satisfactory long-term structural performance, despite having high levels of localized chloride concentrations at the reinforcement. This disparity was noted already more than 50 years ago, but appears still not fully explained. This paper presents a systematic overview of cases reported in the engineering and corrosion literature and considers possible reasons for these differences. Consistent with observations by others, the data show that concretes made from blast furnace cements have better corrosion durability properties. The data also strongly suggest that concretes made with limestone or non-reactive dolomite aggregates or sufficiently high levels of other forms of calcium carbonates have favourable reinforcement corrosion properties. Both corrosion initiation and the onset of significant damage are delayed. Some possible reasons for this are explored briefly.
Reinforcement corrosion initiation and activation times in concrete structures exposed to severe marine environments
Cement and Concrete Research ; 39 , 11 ; 1068-1076
2009
9 Seiten, 58 Quellen
Aufsatz (Zeitschrift)
Englisch
Bewehrungsstahl , Calciumcarbonat , Chlorid , elektrochemische Korrosion , Korrosionseinleitung , Korrosionsprüfung , Korrosionsschaden , Langzeitverhalten , Meeresumwelt , Meerwasserkorrosion , Off-Shore-Anlage , Stahlbeton , Stahlbetonbau , Stahlkorrosion , Träger (Bauwesen) , Übersichtsdarstellung
Characteristic service life for concrete exposed to marine environments
Tema Archiv | 2004
|Effects of Concrete Mix on Initiation of Reinforcement Corrosion and Chloride Threshold Level
Online Contents | 2011
|Effects of Concrete Mix on Initiation of Reinforcement Corrosion and Chloride Threshold Level
Transportation Research Record | 2011
|Corrosion control of existing structures under marine environments
Tema Archiv | 1989
|