Shear strength degradation of vibrated dry sand

The present paper first provides a state-of-the-art review of experimental researches characterizing the shear strength degradation of vibrated dry sand. Once subjected to vibrations, the shear strength of dry sand exponentially decreases with the acceleration amplitude of vibration to reach a particular state wherein dry sand behaves like a complex fluid: this is the vibrofluid behavior. In the present paper, fundamentals equations and criteria governing the shear strength degradation of vibrated dry sand are summarized. A revisited intrinsic Coulomb criterion, taking into account the absence of pore pressure to explain the shear strength degradation, is discussed and explained considering the existence of a corresponding “shaking” pressure. A “general” Critical State Soil Mechanics, including the effect of the acceleration, is introduced. Finally, a rapprochement with the fundamental researches of the physicists involved in the study of granular matter is proposed allowing the identification of the governing dimensionless parameters and the different dynamic regimes encountered by vibrated dry sands once subjected to shearing.