Micromechanism Underlying Nonlinear Stress-DependentK0of Clays at a Wide Range of Pressures

[摘要] In order to investigate the mechanism underlying the reported nonlinear at-rest coefficient of earth pressure,K0of clays at high pressure, a particle-scale model which can be used to calculate vertical and horizontal repulsion between clay particles has been proposed. This model has two initial states which represent the clays at low pressure and high pressure, and the particles in this model can undergo rotation and vertical translation. The computation shows that the majority of particles in a clay sample at high pressure state would experience rotation during one-dimensional compression. In addition, rotation of particles which tends to form a parallel structure causes an increase of the horizontal interparticle force, while vertical translation leads to a decrease in it. Finally, the link between interparticle force, microstructure, and macroscopicK0is analyzed and it can be used to interpret well the nonlinear changes inK0with both vertical consolidation stress and height-diameter ratio.

[学科分类] 材料工程