title: The crucial effect of early-stage gelation on the mechanical properties of cement hydrates.
abstract: Gelation and densification of calcium-silicate-hydrate take place during cement hydration. Both processes are crucial for the development of cement strength, and for the long-term evolution of concrete structures. However, the physicochemical environment evolves during cement formation, making it difficult to disentangle what factors are crucial for the mechanical properties. Here we use Monte Carlo and Molecular Dynamics simulations to study a coarse-grained model of cement formation, and investigate the equilibrium and arrested states. We can correlate the various structures with the time evolution of the interactions between the nano-hydrates during the preparation of cement. The novel emerging picture is that the changes of the physicochemical environment, which dictate the evolution of the effective interactions, specifically favour the early gel formation and its continuous densification. Our observations help us understand how cement attains its unique strength and may help in the rational design of the properties of cement and related materials.
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|MIT-CNRS Joint Laboratory at Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Katerina
authors.initials: K
authors.lastname: Ioannidou
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109 Berlin, Germany.|Department of Theoretical Physics, J. Stefan Institute, SI-1000 Ljubljana, Slovenia.
authors.forename: Matej
authors.initials: M
authors.lastname: Kanduč
authors.affiliation: Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
authors.forename: Lunna
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
authors.forename: Daan
authors.identifier: 0000-0002-6362-2021
authors.initials: D
authors.lastname: Frenkel
authors.affiliation: International Research Center for Soft Matter, Beijing University of Chemical Technology, Beijing 100029, China.|Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Jure
authors.identifier: 0000-0002-1169-6619
authors.initials: J
authors.lastname: Dobnikar
authors.affiliation: Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, District of Columbia 20057, USA.
authors.forename: Emanuela
authors.identifier: 0000-0002-8340-0290
authors.initials: E
authors.lastname: Del Gado