Abstract:"

Development of low-carbon building materials based on ordinary Portland cement (OPC) will require the incorporation of additional materials that have lower carbon footprints than the OPC binders, including soil, clay, and biochar. The incorporation of these materials alter the properties of the resulting cement mix, including the drying and shrinkage properties that can influence cracking. Here, the incorporation of clay into geo-architected cement samples was evaluated for its role on crack formation, growth, and coalescence. The amount of clay shrinkage during drying relative to cement shrinkage during hydration controlled the formation of microcracks driven by debonding at the clay-cement interface, even when the clay was evenly distributed throughout the cement matrix. Therefore, differential shrinkage between multiple phases in cement-composites need to be considered when developing stable cement formulation with the incorporation of additional matrix materials.

Ref: Trageser, Jeremy E., Chven A. Mitchell, Reese E. Jones, Edward N. Matteo, Jessica M. Rimsza, and Laura J. Pyrak-Nolte. "The effect of differential mineral shrinkage on crack formation and network geometry." Scientific Reports 12, no. 1 (2022): 22264.