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Abstract: This work aims to provide a simple semi-probabilistic approach to the service life design of reinforced concrete structures with respect to reinforcement corrosion induced by concrete carbonation. This paper presents an analytical model for the initiation period, calibrated with long-term carbonation results, which uses the accelerated carbonation resistance and the environmental class as input parameters. The issue of defining a limit for deterioration is discussed and a maximum accepted level of deterioration and reliability indexes are defined. The corresponding partial safety factors are derived from a full probabilistic approach. The performance of the proposed method is compared with that proposed on the fib Model Code for Service Life Design. [Copyright &y& Elsevier]

Abstract: In recent years, the number of reinforced concrete structures with anomalies associated with reinforcement corrosion problems has significantly increased. One of the causes is concrete carbonation which occurs when carbon dioxide (CO2) penetrates the concrete’s porous system to create an environment with lower pH around the reinforcement in which corrosion can proceed. Several analytical models describe the relationship between carbonation depth and concrete age, of which the most frequently used results from Fick’s first law: , where K is the carbonation coefficient. This coefficient depends on environmental conditions such as CO2 concentration and humidity and concrete characteristics like w/c ratio, type of cement, and so it varies significantly from one structure to another. A statistical study is presented in this paper to enable a better evaluation of K in open air concrete structures. The study is based on the results of over 100 measurements taken on existing structures up to 99years old. The results were statistically analysed to obtain correlations between K and factors such as structure age, the effect of painting, concrete compressive strength and exposure conditions. This analysis allowed recommendations for the covering of reinforcing bars to be made at design level. [Copyright &y& Elsevier]

Abstract: The financial resources available for infrastructure maintenance and rehabilitation are always limited, creating a need for efficient resource management and for the ability to predict maintenance actions throughout the infrastructure service period. In the context of bridge management, management systems have been developed and are already implemented around the world. Due to a much larger variety of maintenance problems and to a reduced number of buildings per owner, building management systems are still quite rare. In fact efficient methodologies for service life prediction of building materials still need to be developed. This paper presents and tests a service life prediction methodology, based on the statistical analysis of anomalies obtained from the inspection of in-use buildings and the corresponding degradation curves obtained from deterministic models. The method was applied to the service life prediction of paint coatings in old buildings’ façades and considers the quantification of the defect associated to paint peeling. The influence of five construction/environment degradation factors on the behavior of paint coatings over time is also analyzed. [Copyright &y& Elsevier]