Sustainable Concrete Mix Designs for 100-Year Service Life for Bridges in San Diego County Coastal Environments

Deterioration of reinforced concrete structures is a problem in coastal climates. Most of this deterioration is caused by chloride ingress through the concrete, which results in the corrosion of the reinforcing steel and spalling of the cover concrete. The practice of modeling chloride ingress to understand this deterioration process is increasing as engineers work to improve the durability of concrete. The authors present examples of deteriorated structures, modeling results for new structures and examples of current projects along the coastal LOSSAN rail corridor between Los Angeles and San Diego in San Diego County. The conclusion is that by specifying the addition of fly ash, silica fume and corrosion inhibitors in concrete, subject to temperate marine exposure conditions, we are able to increase the predicted service life of new structures to 100 years.