Texture analysis of water-hydrated montmorillonite clay by coarse-grained molecular dynamics simulation

Kimoto, Kazushi*; Kawamura, Katsuyuki*; Makino, Hitoshi 

This study proposes a 2D coarse-grained molecular dynamics (CGMD) method for the compaction simulation of montmorillonite clay. In the CGMD method, a unit structure of a water-hydrated clay molecule is coarse-grained into a particle. Thus, the deformable molecules are modeled as a set of linearly connected coarse-grained particles. As the inter-particle forces, the intra-molecular bonding and inter-molecular van der Waals forces are considered. For simplicity, the intra-molecular bonding is modeled as a linear harmonic oscillator, while the Lenard-Jones potential is used to define the van der Waals force field. With this model, the mechanical compaction of moistured montmorillonite is numerically simulated to find that 4-6 considerably deformed molecules are layered as a result of the compaction. It is alsofound that the simulated XRD pattern agrees to the experiment in terms of the peak angle.