Integrated sensor network for monitoring steel corrosion in concrete structures

Abstract

The developed Integrated Sensor Network (ISN) allows a non-destructive monitoring of the rebar condition at different parts of the structure. The corrosion sensor allows the accurate determination of the corrosion rate (μm/year). Moreover, additional sensors are integrated in order to detect relevant changes in the concrete electrochemical condition.The ISN has been published as an international invention patent (reference number WO 2016/177929 A1). The system is based on an economic, simple, reliable and durable technology, which makes its implementation viable on new and repaired reinforced concrete structures (RCS). Therefore, it is also possible monitoring non-accessible parts such as deep foundations or submerged and buried zones. In any case, no technical personnel are needed because the acquisition, storage and transmission of data is autonomous. In this way, it is possible a remote corrosion assessment of several RCS. In addition, the system needs minimum maintenance works and shows low failure rates.The ISN has been installed for corrosion monitoring of a marine prestressed structure built with Formex®, an Ultra High Performance Fibre Reinforced Concrete (UHPFRC). Five zones of the structure are being monitored. After seven months of monitoring, the corrosion rate (CRATE) stands around 0.2 μm/year, lower than the corrosion rate of the conventional concrete specimens installed (0.5 μm/year). In any case, CRATE is under 1.16 μm/year, the threshold above which the corrosion begins to be considered significant. © ICDCS 2018. All rights reserved.