EXPERIMENT AND DISCRETE ELEMENT NUMERICAL SIMULATION FOR INFLUENCE OF PARTICLE MORPHOLOGY ON SHEAR STRENGTH OF SAND

This paper investigates the effect of particle morphology on the shear strength of sand. We prepared five sets of spherical quartz sand and laboratory standard sand with different particle sizes. Based on the high-performance DEM analysis software MatDEM, we established a three-dimensional direct shear test simulator through deeper development. We compared test data with simulated data. The results are summarized as follows. (1)The natural repose angle of quartz sand has a good positive correlation with its shear strength. (2)Spherical quartz sand can reach the peak strength faster than the laboratory standard sand, but its value is relatively low. Standard sand has a certain cohesion. (3)In the direct shearing process, the displacement of the particles in the middle of the shear box is different from that of the surrounding particles, forming a distinct shear band. The displacement of the particles in the shear band of the spherical quartz sand sample is smaller. (4)The coordination number and shear stress have a good positive correlation. The results of this paper show that under the same conditions, the shear strength of quartz sand with irregular particle morphology is significantly greater than that of spherical quartz sand.