Morphology of Corrosion of Metallic Fibers in Aggressive Media

In marine and industrial environments, the steel bars embedded in concrete can corrode producing the cracking of the cover and impacting negatively in the load-bearing capacity. Metallic fibres have shown a record of good mechanical performance as reinforcing material for concrete. Those on carbon steel can corrode in the aggressive environments and although publications have reported a better impermeability in the fibre reinforced concretes, it still remains the question of how the steel fibres corrode and, in this case,, whether they can microcrack the surroundings. In present communication are presented results of long-term performance of the fibres due to chlorides and carbonation attacks during more than 20 years of exposure. The carbon fibres corrode but not cracking seems to be produced in spite of the full conversion of the fibres into oxides. The galvanized fibres corrode comparatively less, and the stainless-steel ones are in perfect condition.