Nanoscale simulations of rock and clay minerals

Nanomechanics has huge possibilities in explaining basic materials response such as creep, friction, rate and temperature dependency. Constitutive models based on nanomechanics have distinct advantages over phenomological models in simulating the response of geomaterials under extreme environments. This paper presents a study of the elasticity properties of rock and clay minerals using MD simulations. The interatomic potentials used for these minerals are taken from the published work on the same minerals. Both bonded and non-bonded interatomic contributions and periodic boundary conditions in three dimensions are included in the simulations. The elasticity module of the minerals are calculated from the axial stress versus strain curves. The results show that the elasticity properties of the minerals obtained from the MD simulations agree well with the published data. It is found that the elasticity modulus of kaolinite is even higher than quartz, which is in contrast with their known macroscopic properties. This could be due to the arrangement of the clay particles at the microscopic level, which dominates the macroscopic properties of the clay mass. Copyright ASCE 2007.