Modelagem e simulação de dinâmica molecular da tobermorita em condições do pré-sal

Abstract

Some phenomena happen and often go unnoticed by us due to the tiniest scales in which they occur, making it difficult for us to visualize and understand certain subjects. Molecular Dynamics is a method capable of computing atomic movements based on Newton’s equations and Force Field equations that verify the atom-to-atom interactions, whether they are connected or not, enabling the analysis of organic or synthetic molecules. Cementitious materials have been around for a long time, but there are still phenomena in their process that were not clearly understood due to the observation scale. Hydrated Calcium Silicate (C-S-H) is formed in the hydration phase of the grains of cementitious materials and is directly linked to their physical and mechanical properties. Its molecular structure is highly disorganized, which makes us use other systems. Computationally, it has been working with minerals analogous to C-S-H, such as Tobermorita and Jenita, ma- king it possible to perform more precise experiments. Thus, we developed in this work the three-dimensional computational structure of Tobermorita 11 ˚A, its lamellar geometric structure, and parameterization. This work aimed to evaluate the conformation of Tobermorita 11 ˚A in scenarios of high temperatures and pressure similar to those presented in petroleum regions, evaluating thus structural properties. With that, the results showed that the proposed parameterization works for the lamellar structure of Tobermorita 11 ˚A, which made it possible to verify structural deformations and interlayer dehydration with the loss of structural water between lamellas throughout the simulation.