SERVICE LIFE DESIGN OF REINFORCED CONCRETE STRUCTURES

Abstract

Due to rapid urbanization and the rise in greenhouse gas concentrations in the envi ronment, the carbonation of reinforced concrete has gained relevance. Several studies have investigated the carbonation mechanism of Reinforced Concrete (RC) structures and related aspects. However, understanding the deterioration mechanisms and related reasons does not guarantee that RC structures will remain durable for an extended period of time. It is essential to adapt this information to real-world situations. In practice, the partial safety method, which combines the simplicity of the prescriptive design approach and stochastic modelling, is the most realistic design strategy. This study analyses a set of existing struc tures with diverse local environmental variables to determine the partial safety factor for durability of RC structures exposed to carbonation. Depassivation of the reinforcing steel and the first cracking of the concrete cover caused by the corrosion of the reinforcing steel in carbonated concrete are two limit state conditions for which the safety factor is determined. For the depassivation limit state, carbonation depth and concrete cover data are used, while Faraday’s law is applied for the latter limit state in consideration. The goodness-of-fit test provides the best-fit distribution for the variables and then reliability-based analysis is used to establish the partial safety factors.