Infrastructural health monitoring using corrosion sensors: past, present and future

Infrastructural health monitoring (IHM) using corrosion sensors (or probes) is a practical approach to enhancing the safety, durability and economic operation of industrial and civil infrastructures such as underground and submerged oil and gas pipelines. A well designed IHM system is capable of acquiring in-situ and site-specific corrosion data, facilitating early detection and warning of corrosion damage, forecasting and prioritising site inspection and maintenance requirements. The need for IHM is particularly apparent when developing life extension strategies for older infrastructures. Unfortunately the application of corrosion sensors is not always successful, in particular when corrosion sensors are used for monitoring corrosion of infrastructures exposed to complex environmental conditions. This paper aims to provide a brief historical view of corrosion monitoring sensors, and discuss issues and limitations of major forms of corrosion sensors. It is shown that currently the prime challenge in corrosion monitoring is difficulties in simulating and evaluating localised corrosion mechanisms, especially when corrosion mechanisms change with time. Discussion has been extended to future development needs for enhancing the reliability and trustworthiness of corrosion monitoring sensors. Cases have been presented to illustrate potential future corrosion sensor applications with improved design and installation methods as well as with new big data based IHM information technology platforms.