Corrosion mechanism of reinforced bars inside concrete and relevant monitoring or detection apparatus: A review

Abstract It is widely acknowledged that corrosion of reinforced bars is a tremendous challenge against durability performance of reinforced concrete (RC) structures, especially under aggressive environment. Correspondingly, corrosion mechanism has been in-depth investigated all over the world, moreover, amounts of monitoring or detection apparatus have been developed in order to obtain or visualize the damage degree of corroded reinforcements inside concrete, which cannot be recognized by naked eyes. This paper aims to make a short review about corrosion mechanism as well as relevant morning or detection devices based on various physical backgrounds, which include optics, electromagnetism, acoustic, X-ray CT, radar and others. The result shows that much more studies are focusing on the development or upgrading of novel monitoring equipment against reinforcement corrosion, and a revised theoretical model is also putted forward based on non-uniform corrosion type for judging the corrosion-triggered cracks more accurately. Moreover, a suggestive idea has been raised about establishing an intelligent monitoring system which includes novel sensors, data collection and transmission device, and also evaluation procedure as well.