Structural evolution in calcium silicate binders consolidated with calcined clays and alkali

Sustainable binders of low-energy and low-carbon have become of great importance in the search for alternatives to clinker cements which lack sustainability and durability under certain conditions. This project aims to provide a fundamental investigation on the synthesis of novel calcium silicate binders from stainless steel slags and calcined natural clays with the target of transforming them into a single reactive and durable binder system via a chemical activation process using alkali solutions. This particular composite binder couples calcium silicates with alumino silicates and alkalis to favour simultaneous formation of a calcium (aluminate)silicate hydrate (C-(A-)S-H) network, and an alumino-silicate geopolymer network which is known to perform better than a single C-S-H system. It is, therefore, the goal of this research project to deliver fundamental insight in the formation and evolution of this particular binder structure, and in the assessment of its performance behavior. Fundamental aspects related to solidification processes (hydration and polymerization) will be correlated to time-dependent structural evolution and durability properties.  This research will deliver an essential basis for the synthesis of innovative binders with improved durability from calcium-silicate slags and alumino-silicate calcined clays, thereby contributing to the research domain of sustainable and durable construction materials in global and Flemish context.