Significance of particle crushing in granular materials

Particle breakage occurs when the stresses imposed on soil particles exceed their strength. To quantify the amount of breakage, many particle breakage factors have been proposed. Correlations of particle breakage parameters with standard soil parameters such as effective mean normal stress at failure and void ratio at failure do not provide a fully unified correlation with many different types of tests. However, particle breakage factors appear to correlate very well with the total energy input into the test specimen, thus providing a single unifying parameter for all types of soil tests. Therefore, the amount of particle crushing may be predicted if the stresses and strains in the soil can be estimated, such as in a finite-element analysis. The principal significant use of these particle breakage factors may be related to permeability estimates when there are changes in gradation due to particle breakage. A new particle breakage factor, [B.sub.10], is proposed that will allow easy permeability computations when related to the total input energy.