Use of image analysis to study the microstructure of a failed sand specimen

The shearing of dilatant specimens of granular materials in the laboratory is often accompanied by the development of zones of more intense shearing. The nominal behavior of the specimens during this shearing condition is dictated by the behavior of soil particles inside the shear zones. To study the behavior of soil particles inside the shear zones, quantitative evaluation of the soil structure at the particulate scale is required. This paper describes the findings of a study that used digital image analysis to examine sand structure in a specimen where a shear zone formed. Evolution of the local void ratio distribution and changes in particle orientations within and adjacent to the shear zone were quantified.