## 1 Introduction
Traditionally, two types have been used: inhibitors added at the time of mixing, and migratory inhibitors, which are applied externally on the concrete surface and penetrate inside via a diffusion process to reach the level of the re-bars, thus being ideal for rehabilitation operations. Inhibitors added at the time of mixing are mainly inorganic and have been researched since the 1950s, while migratory inhibitors, developed more recently, have gained attention for their usefulness in the restoration of buildings. These inhibitors act by controlling the anodic or cathodic reaction of corrosion, or both, and by providing a barrier against both the dissolution of metal and the reduction of oxygen [13; 36; 37]. There is a third type of corrosion inhibitor that is less used in rehabilitation, and which is applied directly to the reinforcement that is intended to be protected [38; 39; 40]. The research by [PERSON] et al. and other associated studies highlight the significance of migratory corrosion inhibitors and specific coatings like epoxy in improving the corrosion protection of existing concrete structures. It was found that the use of fibre-reinforced mortar-containing corrosion inhibitors introduced at the time of mixing offered superior protection, attributed to the strengthening of the protective passive layer and a reduction in mortar porosity, which decreased the cracking rate thanks to the improved tensile strength provided by the fibres. Additionally, the application of surface coatings, such as epoxy, to reinforcement bars proved to be particularly effective against corrosion in chloride-rich marine environments without compromising adherence to the concrete. These techniques not only prevent the penetration of corrosive agents but also address the issue of the oxidation expansion of steel embedded in reinforced concrete, offering a comprehensive approach to prolonging the lifespan of these structures in the face of environmental aggressiveness [41; 42; 43; 44]. The corrosion of reinforcing steel in reinforced concrete structures is a significant issue that can compromise the integrity and durability of civil infrastructures, such as bridges. In this context, various experimental studies have investigated the corrosion potential of actual reinforced concrete structures, using guidelines established by the ASTM for the evaluation of corrosion and the interpretation of the results obtained. The authors [PERSON], [PERSON], and [PERSON] (2023) explore the effects of corrosion on the seismic vulnerability of reinforced concrete bridge piers in their article \"Assessment of Seismic Vulnerability of Reinforced Concrete Bridge Piers with Corrooded bars\". This study provides valuable insights into how corrosion affects load-bearing capacity and structural resilience in the context of seismic events, utilising experimental data based on ASTM guidelines and additional relevant studies. Additionally, in their article \"Recent Advances in the Use of Green Corrosion Inhibitors to Prevent Chloride-Induced Corrosion in Reinforced Concrete\", [PERSON] et al. (2023) present a review of the latest advances in the development and application of environmentally friendly corrosion inhibitors with which to mitigate chloride-induced corrosion in reinforced concrete structures. This work highlights the importance of seeking sustainable and effective solutions in order to combat corrosion in civil infrastructures. Both studies complement the current understanding of corrosion challenges in reinforced concrete structures, providing valuable insights for the design, maintenance, and management of these key infrastructures (45; 46). A study conducted by [PERSON] et al. (2020) shows that the effectiveness of corrosion inhibitors injected at high pressures into hardened concrete is directly influenced by the water/cement ratio of the concrete. It was determined that concrete with a higher water/cement ratio allows for deeper penetration of the inhibitor when a prolonged pressure time is applied.