Theoretical study about Calcium Silicate Hydrate (C-S-H) anisotropy growth

Identifier:  TFG:1176

Handle: https://hdl.handle.net/20.500.11797/TFG1176

Authors:  Alías Rodríguez, Marc

Abstract:
Abstract Calcium silicate hydrate (C-S-H) is the main phase in concrete. The size of the system, in the order of nanometres, and its non-ordered disposition are responsible of concrete’s harden. C-S-H particles have a limited size and very anisotropic shape. The atomic structure of C-S-H is known only for the bulk. In the current work an atomistic study of C-S-H growth in the different directions was performed. C-S-H particles with different sizes were created and their energy was computed in molecular mechanics method through ReaxFF as force field and semi-empirical method through PM6 as Hamiltonian. The results show anisotropy: the growth in x and y direction is preferable than in z direction. It shows anisotropy growth and confirms C-S-H particles’ shape is as a pancake forming platelets. The size of computed particles is still in order of magnitude smaller, and thus it is not possible to have conclusions about the limited size of C-S-H particles.