Experimental study on the 3D vibrated packing densification of binary sphere mixtures

Abstract The packing densification of binary spherical mixtures under 3D mechanical vibration was studied experimentally. The influences of vibration frequency ( ω ), volume fraction of large spheres ( X L ), sphere size ratio ( r , diameter ratio of small to large spheres), and container size ( D ) on the random binary packing density ( ρ ) were systematically analyzed. For any given set of conditions, there exist optimal ω and X L to realize the densest random binary packing; too large or small ω and X L is not helpful for densification. The influences of both r and D on ρ are monotonic; either reducing r or increasing D leads to a high value of ρ . With all other parameters held constant, the densest random packing occurs when X L is dominant, which is in good agreement with the Furnas relation. Moreover, the highest random binary packing density obtained in our work agrees well with corresponding numerical and analytical results in the literature.