EXPERIMENT AND DEM NUMERICAL SIMULATION FOR INFLUENCE OF PARTICLE SIZE DISTRIBUTION AND SHAPE ON COMPRESSIBILITY OF SAND

Abstract

To study influence of particle size distribution and shape on compressibility of sand, we used spherical quartz sand and laboratorial standard sand with irregular shape as materials to do confined compression test of specimens prepared by sand pluviation method, then used MatDEM,the 3D DEM software developed by our research group, to do numerical simulation. Specimens with various particle size distributions revealed influence of particle size, particle size range, relative size and content of fine grains on compressibility of sand, while control experiments between spherical quartz sand and laboratorial standard sand revealed the one of particle shape. On this basis, combined with numerical simulation, the results indicate that:There is a non-monotonic relation between particle size and compressibility. The wider the particle size range is,the greater compressibility the specimen prepared by sand pluviation method will show. The reduction of relative size and content of fine grains will both increase the compressibility. Particle shape will influence the specimen prepared by sand pluviation method, which makes laboratorial standard sand show greater compressibility under low stress and then converge with spherical quartz sand. The 3D DEM software MatDEM can simulate the process of sand confined compression test effectively, which provides a reference for future study of DEM numerical simulation in geotechnical engineering.