Modelling concrete deterioration in sewers using theory and field observations. (November 2015)

• Record Type: Journal Article
• Authors: Wells, T.; Melchers, R.E.
• Is Part Of: Cement and concrete research. Volume 77(2015)
• Page Start: 82
• Page End: 96
• Publication Date: 2015-11
• Subjects: Reaction (A) -- Corrosion (C) -- Concrete (E) -- Modelling (E); Cement -- Periodicals; Cement -- Research -- Periodicals; Concrete -- Periodicals; Concrete -- Research -- Periodicals; Ciment -- Périodiques; Béton -- Périodiques; Cement; Concrete; Periodicals; 620.135
• DOI: 10.1016/j.cemconres.2015.07.003
• Languages: English
• ISSNs: 0008-8846

Abstract

Abstract: Samples of new and 70 year old pre-corroded OPC concrete were exposed for up to 48 months in 6 sewers throughout Australia. Corrosion losses at each site followed the bi-linear trend originally proposed by Wells and Melchers [1]. During an initial phase (lasting < 2 years) negligible loss of material occurs however once the surface pH = 6 losses commence and accumulate linearly at a rate that is likely to remain constant over time. Corrosion rates were found to be sensitive to humidity but insensitive to concrete alkalinity. A first pass model which predicts the rate of concrete sewer pipe corrosion from a knowledge of local average sewer gas temperature, humidity and H2 S concentrations was also developed. The equation predictions were in good agreement with rates determined from field observation and historical data.