SGER: Evaluation and Modeling of Interlayer Forces in Montmorillonite For Development of a Particulate Based Model for Swelling Clays

North Dakota State University Fargo, Fargo ND

Investigators

Abstract

The understanding, modeling and prediction of interaction of clays with water and other environmental fluids is an important issue in the field of geotechnical engineering, geoenvironmental engineering as well as industrial applications such as muds for oil well drilling and water treatment. The swelling response of saturated montmorillonite and the corresponding development of swelling pressure when swelling is restrained is the result of fairly complex interactions a) within the interlayers of the clay particle and b) the interactions between the particles. The recent advances in experimental, analytical and computational mechanics areas will allow the PIs to model and simulate these complex interactions and allow for prediction of the swelling response using Discrete Element Method (DEM). The PIs plan to consider both the interlayer and interparticle interactions. The interlayer interactions will include silica-water interactions including hydrogen bonding at silica-water interface and the hydrogen bonding between water molecules in the interlayers. This focus of this work is to understand and model the significant interlayer forces in montmorillonite clay during hydration and swelling to provide a foundation for the development of particulate based models for swelling clays. A combination of analytical characterization techniques [Fourier transform infrared spectroscopy (FTIR), X-ray diffraction and scanning electron microscopy (SEM)] and analytical description of forces from classical physics will be used for implementation into DEM.