Ion-ion correlations and charge reversal at titrating solid interfaces

2009

International audience

Experimental and Theoretical Evidence of the Overcharging in Calcium-Silicate-Hydrate

2006

International audience

Thermodynamic and structure properties of clay dispersions : A Monte Carlo study

2010

International audience

Adsorption of multivalent ions in cementitious materials : Importance of electrostatics

2008

Acid-base properties of 2:1 clays: The role of electrostatics

2010

International audience; We present a theoretical and experimental investigation of the titratable charge of 2:1 clays with various structural charge ('b): pyrophyllite ('b = 0 e. nm(2), montmorillonite ('b = -0.7 e. nm(2) and illite ('b = -1.2 e. nm(2). The calculations were carried out using a Monte Carlo method in the Grand Canonical ensemble and in the framework of the primitive model. The clay particle was modeled as a hexagonal platelet, with an ‘ideal' crystal structure. The only fitting parameters used are the intrinsic equilibrium constants for the protonation/deprotonation reactions of the broken-bond sites on the lateral faces. Simulations are found to give a satisfactory descript…

The Cement Cohesion: an Affair of Electrostatics

2007

International audience

Charge reversal and charge regulation at silica surfaces

2010

International audience

Colloidal Behavior of C-S-H Nanohydrates in Cement Paste

2010

International audience; Among the hydrates constituting a cement paste, C-S-H is the main component, it represents at least 60 % of the fully hydrated paste. C-S-H has a lamellar structure similar to that of a rare mineral, tobermorite. The germination and growth of the C-S-H particles result in increasing mechanical resistance (strength, cohesion). Mechanical experiments show that the intrinsic properties of the paste remain the same throughout the hydration process. Indeed, despite its very high compression strength properties the hydrated cement paste retains the same very low critical strain (~10 -4) characterizing a small elastic limit of the material. More recently, AFM experiments ha…

On the Charging Process of Minerals

2007

International audience