Service life design of concrete structures according to FIB model code – concept and practical application

Abstract

Concept and procedure of service life design of reinforced concrete structures is presented in the paper. The aim of this concept based on probability is to bring the durability design at the same level with the design to ultimate limit state or serviceability limit state. The design follows the three-step procedure – diagnosis of the deterioration mechanism that would have the greatest impact on structure, definition of the limit state for design and verification of a limit state. All the parameters of the model, both on the load side (the environmental actions) and on the resistance side (the resistance of the concrete against the considered environmental actions) must be statistically described and quantified, to enable verification of considered limit states with probabilistic methods. Concept of service life design is demonstrated with selected deterioration mechanism – carbonation of concrete and selected limit state- depassivation of reinforcement. All parameters are described and their impact is assessed. Numerical examples, i.e. several case studies are presented in the second part of the paper. There are two situations – service life design of a new structures and assessment of the rest of service life of existing structure.