Quantification of surface roughness of granular materials – A new approach using Gaussian filter

Abstract

The mechanical response of a granular assembly such as sandy soil is affected by the surface roughness of its constituent particles. However, such research has not been sufficiently conducted due to a lack of objective approaches to quantify the surface roughness. Recent advancement of optical interferometry technique enables accurate measurements of nano-order surface roughness. A difficulty is that surface roughness should be evaluated on the surface texture, isolated from the overall curvature of the grain shape. This contribution proposes a new objective approach to quantify the surface roughness of non-planar surfaces using Gaussian filter.