Thomas Matschei
Bio
Thomas Matschei is professor for construction materials at the Institute for Building Materials Research (ibac) at RWTH Aachen University. After studying civil engineering, specialized in building materials and renovation, he obtained his PhD at the University of Aberdeen /UK in cooperation with EMPA Dübendorf /CH in the field of cement chemistry in 2008. From 2008 he worked in various positions in the cement industry. In addition to activities in research and development, he was responsible for a team for the application of new cements and binders and worked as a building segment manager. From 2017 to 2020 he worked as a professor for concrete building materials at HTW Dresden. In 2020 he accepted a professorship for construction materials at RWTH Aachen University. His research focusses on sustainable low carbon binder and concrete systems.
KeyNote
Advances in Understanding Cement Hydration and Thermodynamics of Hydrated Systems
Abstract
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.