Corrosion behavior of reinforcement in a 8-year old prototype made with seawater concrete

To address water shortages occurring in different parts of the world, the SEACON-Infravation project developed the idea of combining the use of seawater, instead of potable water, and other chloride-contaminated constituents, which are currently forbidden by standards and codes, with various types of corrosion-resistant reinforcements for the construction of sustainable and durable reinforced concrete structures. The project included an intensive laboratory campaign and the execution of two demo projects – one in Italy and one in Florida – with the aim of testing seawater concrete on-site. The prototype structure built in Italy consisted in a culvert for the collection of a highway wastewater, potentially contaminated by chlorides resulting from the use of de-icing salts during the winter period. The culvert was divided in six individual segments representative of a combination of type of concrete, i.e. traditional concrete, concrete mixed with seawater, and concrete produced with recycled asphalt pavement, and type of reinforcement, i.e. carbon steel, GFRP, and stainless-steels of two grades. Although the project is already ended the monitoring of the corrosion conditions of prototype is still on-going to evaluate the long-term behavior of concrete reinforcement. This paper discusses the evolution of the reinforcement conditions over a period of almost 8 years.