Behavior of reinforced concrete structures Corrosion of rebars

After the Second World War, there was a great need for infrastructure. Faced with the challenge of reconstruction, public authorities turned to architects and civil engineers, who had to provide rapid responses. In this context, the answers they came up with sometimes failed to fully integrate the notions of durability of civil engineering structures. Today, all these infrastructures constitute a legacy and a heritage whose functionality in service must be maintained.

Examples include engineering structures and rail bridges used by all road and rail users. However, as mentioned in the Senate information report , structure managers have reported significant signs of damage caused by the interaction between the external environment and the materials making up existing structures. Their durability is clearly affected, sometimes leading to a loss of serviceability or even structural safety. One of the major causes of this loss of performance has been identified as corrosion of the reinforcement present in reinforced concrete. This phenomenon is liable to develop either through carbonation, or through the penetration of chloride ions into the embedding concrete. This is when corrosion products, also known as rust, appear. Their formation and subsequent expansion generate tensile stresses which, once the concrete's tensile strength is exceeded, lead to the appearance of cracks. From a practical point of view, as soon as the first cracks are noticed on the concrete surface, corrosion has generally reached an advanced stage, and corrective maintenance actions need to be launched. This entails significant costs .

In this way, the evolution of the mechanical consequences associated with the development of corrosion in reinforced concrete reinforcement can be considered in the case of existing structures. Moreover, based on the experience acquired since the 1950s, this point must be taken into account for new structures of all types (design, in-service monitoring, maintenance). Providing answers to the question of how best to anticipate the consequences of this pathology is therefore a major challenge. To this end, a great deal of work has been carried out by national and international scientific communities. Examples include the APPLET ,...