This research study is motivated by the long-term need to develop truly sustainable concretes for a cement reduction target of 40-70 percent (mass-basis) that demonstrate early/later age properties comparable to their pure-cement counterparts. As such, multiple-material solutions will be developed to optimize the use of abundant, naturally occurring, materials such as limestone (powder) to produce concretes with highly reduced cement contents. The scientific approach exploits carboaluminate phase formation to ensure an increase in the solid volume of reaction products and a reduction in the porosity, when a favorable binder chemistry exists. Thermodynamic calculations will be used to predict the equilibrium solid/liquid phase assemblages of the modified binder systems. The calculations will be validated against kinetic, microstructural and phase characterization studies. Further evaluations of the physical and engineering properties will be carried out to develop analytical tools for property prediction. Specifically, aspects related to the mechanical and transport behavior will be evaluated to develop material models which relate the physical aspects of the microstructure and the overall binder chemistry to the engineering properties as relevant for practical construction applications. The development of chemical composition-microstructure-engineering property relationships will enable the advancement of property prediction tools and thus ensure the wide-spread use of these concretes in concrete construction applications.
The outcomes of this research will enable the development and deployment of the next generation of sustainable concrete materials with desirable engineering properties and provide tools for their prediction thus providing structural designers, contractors and concrete producers the confidence needed to widely specify and deploy sustainable, low-CO2 construction material solutions. This is significant as facilitating the use of concretes with a low-cement content will change the way sustainability metrics are considered from a materials perspective in the concrete construction industry. From an educational perspective, this research will support the training of under-represented and minority Ph.D and undergraduate students at the collaborating institutions. Rapid dissemination of the research to the broader research and practicing community will be accomplished through scientific publications and presentations, industrial workshops and professional education courses.
