We are interested to study how waves propagate in a granular material in a dry or fully saturated condition. Our analysis is based upon a micro-mechanical approach whose goal is to derive accurate mathematical descriptions of the mechanical behavior of the aggregate. We employ force and torque equilibrium for a typical pair in order to determine its proper kinematics. Then it is possible to derive an average stress for the aggregate to attempt to predict: wave speeds, stress-strain relation, volume change, anisotropy, localization. In case of fully saturated aggregate our model is also able to predict slow compressive waves in case of sediments.

Numerical simulations, based on the D.E.M. (Distinct Element Method), supports and guides our modelling.

We are in collaboration with Office of Naval Research to start an experimental activity to study compressive and shear waves in sediments and consolidated granular aggregates.

Collaborations:

James Thomas Jenkins, Cornell University (USA)

Giuseppina Recchia, Politecnico di Bari (Italy)

Vanessa Magnanimo, University of Twente (Netherlands)

Hongyang Cheng, University of Twente (Netherlands)