The Influence of the Binder Type & Aggregate Nature on the Electrical Resistivity of Conventional Concrete

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Concrete has been increasingly used in a number of civil engineering applications due to its interesting fresh,**hardened and durability-related properties. Compressive strength, normally measured at 28 days, is the most**important hardened state property of concrete and is often used as an indicator of its "microstructure quality".**On the other hand, pressure is mounting in the construction industry to optimize construction scheduling and**reduce delays which makes imperative to have a fast, thorough and reliable control of the "early-age" properties**of the material. Numerous advanced techniques have been proposed in this regard, and it has been found that**electrical resistivity (ER), a non-destructive and inexpensive technique, is able to characterize microstructure**development and thus evaluate mechanical and durability-related properties of cementitious materials, such as**concrete, over time. Conversely, recent literature data have evidenced that ER may be significantly influenced**by a variety of parameters such as the test setup (i.e. surface resistivity vs bulk resistivity vs internal resistivity),**material porosity and moisture content, binder type/amount and presence of supplementary cementing materials**(SCMs) along with the nature of the aggregates used in the mix (i.e. magmatic vs. metamorphic vs.**sedimentary rocks), which complicates the practical benchmark of concrete mixtures proportioned with distinct**raw materials. In this context, Giatec Scientific Inc. is a world-leading Ottawa-based company that uses**cutting-edge technologies of wireless sensors and mobile apps to collect a variety of data related to concrete.**One of the most promising markets for Giatec is the measurement of ER in conventional concrete and its**correlation with the mechanical properties of material over time (e.g. compressive strength). Giatec is currently**seeking the expertise of a concrete materials expert such as the applicant through a first-time collaboration to**study the impact of the binder type/amount and aggregate's nature on the ER response of conventional concrete**mixtures presenting a wide range of raw materials. The research results will help Giatec to enhance its current**ER device, increase the accuracy of the test outcomes and improve the overall quality of the services offered to