ABSTRACT
In this paper, collapse behaviour of gravelly material is investigated. The main focus is the effect of particle shape on the strength and collapse parameters of angular and sub-angular gravelly material. The effects of normal stress and shear stress levels are also investigated. For this purpose, direct shear apparatus was employed and several tests were conducted on dry, saturated and dry samples followed by saturation during shearing, with the later called collapse test in this study. In the collapse tests, the materials were compacted dry and subjected to normal stress and sheared; then, they were saturated at specific shear Stress Levels (SL) and shearing resumed thereafter. Most of the tests were conducted on samples subject to three normal stress levels with the same relative density. Samples with sub-angular particles and angular particles of the same origin and gradation curves were prepared. For both types of material, index and physical properties were determined for the purpose of sample preparation. Results of the direct shear tests are discussed on both stress and deformation characteristics of the soil samples.
