Effects of Oversize Particles on the Density of Clean Granular Soils
Fill material often contains particles too large to be tested in conventional testing equipment. In order to evaluate the compaction, strength, and deformation characteristics of soil containing such oversize particles, a modeling criterion is required which specifies how the soil minus the oversize particles (the soil matrix) should be tested. Questions such as whether or not to replace oversize particles with particles just large enough to be tested and at what density should the model material be prepared must be addressed by such a modeling criterion. To develop modeling criteria it is necessary to know how the oversize particles affect the density of the total material. This paper presents the results of a study which shows that oversize particles increase the void ratio of the soil matrix in a manner which is affected by the relative density of the soil. Both theoretical and experimental work are described which lead to the development of a method for predicting the density of the soil surrounding oversize particles as a function of the relative density of the entire soil sample and the percentage of oversize particles.