The Synergy of Electrochemistry and Concrete Material Science in Evaluating Corrosion Resistance of Wastes-Containing Reinforced Cement-Based Systems

Next to water, concrete is the most used material on earth. Reinforced concrete has the potential to be durable and capable of withstanding a variety of adverse environmental conditions. One of the major difficulties in the engineering practice, however, is the multidimensional nature of reinforcement corrosion related issues. Nevertheless, materials and processes involved in the service life of a civil structure and their interaction are independently weighed and are seldom brought together. Very often the design of concrete mix proportions and the design of protective measures (such as the application of coatings or electrochemical techniques) are made in separate steps and (positive or negative) interactions among themselves are neglected. The most original aspect of this work is the integration of fundamental electrochemical techniques and concrete material science within monitoring and assessment of the corrosion performance of reinforced cement-based materials. Further, hereby discussed is the implementation of an eco-friendly approach of waste utilization for corrosion control and/or achieving superior properties and performance. Reinforced cement-based systems (e.g. reinforced mortar and concrete) are multi-phase composite materials at different levels of aggregation. Hence, multi-phase interfaces are involved in their structural performance and material behaviour. The steel reinforcement is embedded (on meso-level, generally relevant to mm dimension) in supposedly homogeneous cement-based bulk matrix. However, on a lower structural level (micro-level, expressed in μm), the bulk material consists of cement paste and aggregate particles, with air voids and macro pores dispersed in the cement paste matrix. Further, the cement paste can be decomposed into un-hydrated cement, hydration products, and capillary pore structure. The latter is generally assumed to have significant relevance to permeability and other transport phenomena in concrete technology. Both the reinforcement corrosion processes (i.e. electrochemical phenomena) and the development of the cement-based microstructure are influencing the material structure in reinforced cement-based materials (as mortar or concrete) on macro and micro/nano level. The corrosion process on one hand and hydration mechanisms on the other, determine changes in microstructural properties and ion transport, compared to rest conditions (in