Implementation of Remote Corrosion-Monitoring Sensor for Mission-Essential Structures at Okinawa

Abstract : This project demonstrated innovative remote sensors (LPR sensors) the size of postage stamps which can provide instantaneous corrosion rate data from under a coating. These sensors were installed beneath a coating on a mission-critical metal structure roof in Okinawa, to detect the intrusion of moisture and predict the corrosion rates from the shifts in polarization resistance. With this real-time data capability, early detection of the need for maintenance on the structure can be determined and corrections made, extending the service life of the structure and lowering life-cycle cost. This technology is applicable to metal roofs, water tanks, fences or any metal structures that early detection of corrosion is needed to extend the life of the structure, avoid costly early replacement or avoid complete failure of the structure. Standard coupon tests and electrical resistance (ER) probes provide corrosion rates at a lower cost than the LPR sensors but not instantaneous rates as do the LPR sensors. Standard coupon and ER probes were demonstrated on this project for comparison to LPR corrosion rate data and to obtain atmospheric corrosion rates in this highly corrosive environment.