A study of sand penetration in clay slurry

When sand is spread onto a clay slurry, the mechanics of sand penetration is a complicated problem and is studied in this paper via a model of a sphere settling in a slurry. The analytical results show that the initial impact velocity affects only the entry into the clay and the subsequent penetration of the particle is controlled by its buoyant weight versus the shear resistance from the slurry. This led to the development of a dimensionless parameter, which is the ratio of the shear resistance over the buoyant weight of the sand spread, to analyze the experimental data. This analysis indicates that the finer particles are trapped at the upper part while the larger particles penetrated more deeply. A weighted mean diameter was used in the analytical model to reflect the grain size distribution of the sand. The results from this was found to agree well with both experimental and field data.