A statistical treatment has been applied to a deterministic service life model of concrete structures in marine environments. The chloride ingress model based on Fick's second law of diffusion was assumed. The quality of concrete was quantified in terms of three factors, namely, an apparent diffusion coefficient at 1 year (Da ), surface chloride concentration (Cs) and a critical chloride level (Ccr). The standard deviation of service life can be estimated from standard deviations of the four factors, namely, Cs , Da, Ccr and cover depth. The effect of the severity of environment on service life was also demonstrated. With data from the literature and an approximation of the inverse error function, sensitivity analyses were carried out. Service life was found to be more sensitive to cover depth than the diffusion coefficient, and more sensitive to surface chloride concentration than the critical chloride level. Characteristic service life of a range of normal Portland cement (NPC) concrete grades was evaluated as a function of 28-day strength and cover depths for a nominated confidence level. Such characteristic service life can be readily used and appreciated by design engineers.
Characteristic service life for concrete exposed to marine environments
Cement and Concrete Research ; 34 , 5 ; 745-752
2004
8 Seiten, 32 Quellen
Aufsatz (Zeitschrift)
Englisch
Marinetechnik , Lebensdauer , Diffusion , Portlandzement , Meerwasser , Zufallsprozess , statistisches Verfahren , Approximationstheorie , Fehleranalyse , mathematisches Modell , Standardabweichung , stochastisches Modell , Meeresumwelt , Fehlerfunktion , Lebensdauervorhersage , Beton , Ficksche Diffusion , Ficksches Gesetz , Chloridkorrosion
Concrete Bridge Service Life Extension Using Sealers in Chloride-Laden Environments
Online Contents | 1996
|Concrete Bridge Service Life Extension Using Sealers in Chloride-Laden Environments
Transportation Research Record | 1996
|Concrete Bridge Service Life Extension Using Sealers in Chloride-Laden Environments
Transportation Research Record | 1996
|