Abstract
Reinforced concrete is the world's most widely used building material for several reasons: excellent mechanical properties, relatively low manufacturing cost and high availability of raw materials [1]. Durability is another char-acteristic that distinguishes reinforced concrete from other materials. This property refers to the ability to maintain its performance regardless of service or exposure conditions [2,3].
Over the last few decades, reinforcement corrosion has been identified as one of the main causes of deterioration and durability loss of reinforced concrete structures [4]. It is a common electrochemical process that is associated with high economic costs for repairs or demolitions [5]. Corrosion of the reinforcement causes steel section loss, rust stains on the material¿s surface and cracks in the concrete cover. In some cases, when the damage is advanced, spalling or splitting of the concrete cover is also common [6]. Although it is a complex phenomenon, it is commonly accepted that its onset depends on the resistance of the material to the penetration of corrosion precursors (chlo-rides or carbonation) [7]. On the other hand, when reinforcement corrosion has already started, it is the concrete resistivity that acts as the governing factor [8]. This is because it is a property that relates parameters such as mois-ture content or the porous structure of the cementitious matrix.
The present work studied two columns manufactured with different concretes (CEM II and CEM III). The pieces were partially submerged in seawater allowing different local exposure conditions to be generated: submerged zone, tidal zone, splash zone and aerated zone. Under this set-up, concrete resistivity was monitored for more than a year using embedded sensors. The results made it possible to relate the corrosion probability of the embedded reinforcement in each part of every column.
