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This paper provides an approach based on the monitoring of life cycle performance of concrete bridges exposed to chlorides, and demonstrates its application in a case study. It is first shown that some of the data, which are commonly used by engineers as input values into service life prediction models, can be different from actual field values, because these parameters vary widely in space and time. It is then demonstrated that service life predictions can be improved by updating the models with field monitoring data., 6th International Conference on Concrete under Severe Conditions, Environment & Loading (CONSEC'10): 7-9 June 2010, Mérida, Yucatán, Mexico

A considerable percentage of highway bridges in North America is in a structurally/functionally deficient state due to aging, aggressive environment and increased traffic load and volume. The consequences of this deficiency are numerous, including reduced safety, serviceability and service life, which lead to increased risk of injuries and fatalities; and increased maintenance costs and user costs. Reliable predictions of life cycle performance are critical to the optimization of their design and maintenance that will lead to reduced risks of failure and life cycle costs., Annual Conference of the Transportation Association of Canada (TAC): 21 September 2008, Toronto, Ontario

High performance concrete (HPC) bridge decks are prone to premature cracking if movement is restrained. Internal curing (IC) can reduce shrinkage cracking in structures, thus improving their performance and service life. However, there is very limited information in the literature on the possible extension of service life due to internal curing. This paper addresses this question by using predictive models to estimate the service life and life-cycle costs of a typical bridge deck made with concrete using internal curing as opposed to conventional curing. Four options are compared: (i) normal concrete deck; (ii) HPC deck; (iii) HPC deck with internal curing; and (iv) very high performance concrete deck with internal curing. It was found that the use of internal curing can extend the service life of HPC bridge decks by almost ten years, which is mainly due to due a slower penetration of chlorides as a result of reduced shrinkage cracking. The use of internal curing in HPC decks resulted in a 20% reduction in life-cycle costs, even though the in-place unit cost of internally-cured HPC can be up to 4% higher than that of conventionally-cured HPC. The higher initial investment for the construction of the HPC-IC deck can be offset in only 5 years when compared to that required for normal concrete deck. This is due to a longer service life and less frequent maintenance activities., 50th Brazilian Concrete Congress "Concrete Infrastructure and Environmental Conservation": 04 September 2008, Salvador, Brazil

Construction and the Environment - CIB World Building Congress: 07 June 1998, Gavle, Sweden