Effect of nano-silica particles on the hydration, the rheology and the strength development of a blended cement paste

F. Lavergne (1) , R. Belhadi (1) , J. Carriat (1) , A. Ben Fraj (1)

1 Cerema Equipe-projet DIMA - Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet DIMA

The aim of the present work is to evaluate the effect of nano-silica (NS) on the hydration, the rheology and the strength development of cement pastes. The advance of chemical reactions is monitored by mean of isothermal calorimetry and thermogravimetric analysis: adding nano-silica particles speeds up the hydration of the cement paste but alter its workability. Indeed, the effect of the nano-silica particles on the hydration kinetics can be modelled by accounting for its high specific surface and a flocculation model based on the DLVO theory is proposed so as to investigate the stability of nano-silica suspensions in the fresh cement paste. As a consequence, the dosage of nano-silica can be optimized to promote the early age strength. Lastly, a ternary blend incorporating fly ash can be designed so as to provide an early age strength similar to that of the cement while lowering the induced CO 2 emissions.

Mots clés: nanoparticles; hydration; strength; flocculation

Domaines: Mécanique des matériaux [physics.class-ph]; Génie civil; Matériaux

F. Lavergne, R. Belhadi, J. Carriat, A. Ben Fraj. Effect of nano-silica particles on the hydration, the rheology and the strength development of a blended cement paste. Cement and Concrete Composites, 2019, 95, pp.42 - 55. ⟨10.1016/j.cemconcomp.2018.10.007⟩. ⟨hal-01900692⟩