Karen Scrivener has been Professor and Director of the Laboratory of Construction Materials in the Department of Materials of EPFL(Ecole Polytechnique Federale de Lausanne for the last 20 years. She is a Fellow of the UK Royal Academy of Engineering and author of over 200 journal papers. Her research focusses on the understanding the chemistry and microstructure of cement based materials and improving their sustainability. In 2008, she came up with the idea for LC3 cement, this material has the potential to cut CO2 emissions related to cement by more than 400 million tonnes a year. She received her bachelor’s degree in Materials Science from the University of Cambridge in 1979 and her PhD from Imperial College London in 1984.
Advances in Understanding Cement Hydration and Thermodynamics of Hydrated Systems
Hydration is the fundamental process which transform cementitious materials from fluid slurries to strong durable materials. This paper review advances in our understanding of cement hydration and the thermodynamics of hydrated systems. First we review the progress in the understanding of the main hydrate phase C-S-H where atomistic modelling has made a major contribution in recent years. Then we look at the early stages of C3S hydration including dissolution pathways and the formation of C-S-H. We will discuss the importance of aqueous complex formation during early precipitation of C-S-H. Moreover new developments in understanding the role of aluminate, ferrite and belite in cement hydration are highlighted. We will focus explicitly on the solid solutions amongst AFm-phases as well as between AFt phases and highlight their impact on the thermodynamic phase- and mass balance relations of hydrated cements. Next we look at the reaction of the common supplementary cementitious materials in cementitious systems and finally the evolution of the microstructure and phase assemblages at late ages. Throughout the paper related thermodynamic aspects are taken into account and will be discussed.