Chloride ion detection in concrete through galvanic and resistivity methods

Abstract

The construction industry has a significant impact on the environment with increasing consumption of resources. The degradation of reinforced concrete structures when exposed to different environmental conditions affects the life-time of structures and presents significant challenges in the construction industry. More sustainable construction methods are necessary to improve durability and resilience of structures. Resilient structures can be achieved through the development of systems which are autonomously able to detect harmful chemical substances in time, to enable remedial action to be undertaken, thus avoiding structural degradation. This paper reviews and explores two methods of chloride ion detection, namely the voltage produced by a galvanic pair of metals under the influence of chloride ions, and the change in resistivity which an influx of chloride ions produces in the actual concrete. This paper explores the harnessing of such methods in the development of a sensory platform used for the detection of chloride levels beyond a threshold level. Such a platform should be able to perform autonomously from a power supply and have the potential for long term monitoring of the concrete structure ́s performance.