A Chemometric Approach for the Optimization of Low Carbon Concrete Admixtures with Blended Cements

The roadmap to carbon neutrality of concrete provides, as one of the main actions, the partial replacement of clinker by supplementary cementitious materials (SCMs) in blended cements. Most SCMs are characterized by a much lower carbon footprint compared to clinker and therefore blended cements represent the best solution for producing concrete with low carbon content (LCC, Low Carbon Concrete). Recently, a new class of Low Carbon Concrete Admixtures (LCCAs) has been developed to compensate the loss of both early and final strength of blended cements in comparison with ordinary Portland cement (OPC). Different formulations of LCCAs have been proven to be effective in activating blended cements, some of them for improving early strength, others for enhancing final strength, or both. In the present work, a chemometric approach was used to highlight specific admixture-binder interactions aiming to identify the most effective LCCA for different blended cements. The application of Principal Component Analysis (PCA) and Design of Experiment (DoE) on datasets of compressive strength of mortars prepared with different blended cements and different LCCAs allowed to identify specific interactions related to the chemical composition of blended cements and to optimize the formulation of LCCAs for specific applications.