Large landslides occur after an energetic trigger event, such as earthquakes and volcanic eruptions, which activates a mechanism called "acoustic fluidization", in accordance with a theory developed by the principal investigator. He has demonstrated that acoustic energy does facilitate the flow of rock debris in some preliminary experiments. Still, one of the major areas of uncertainty in this mechanism is the value of certain important material parameters that describe the production, scattering, and ultimately the loss of vibrational (acoustic) energy in a mass of lose rock debris. An experimental program to evaluate these parameters in the laboratory will be undertaken in which the stress-strain rate relation in a vibrating mass of debris will be measured, the physics of wave propagation and scattering in the debris will be studied, and the rate at which energy is lost by internal dissipation and gained during shearing of the debris mass will be estimated. This work will provide a better understanding of large-scale gravitational land failures.
