Fluidization in dry landslides

This paper aims at determining the physical properties affecting the distan ce travelled by landslides with dry particles, and elucidating the mechanis m of the properties affecting landslide fluidization. The procedure is as f ollows: laboratory landslide experiments were conducted to verify the simul ation model which was proposed to represent the movement of landslides. Fur ther, sensitivity analysis for some physical properties affecting the trave l distance were conducted using this model. The simulation model could iden tify the coordinates, velocity and angular velocity for every particle in t hree-dimensional space, and the kinetic energy of particles consumed by ine lastic and frictional collision with each other in the model. The travel di stances of landslides simulated by the model were verified by laboratory ex periments statistically where the physical properties for the particles and slope angle were changed. Then, sensitivity analysis for the physical prop erties were conducted using the model to clarify the effect of the properti es on the travel distance. It was proven that there were no significant dif ferences between the travel distances represented by the simulation model a nd those found experimentally using statistical analysis (i.e. the simulati on model could represent virtual real landslides). From the sensitivity ana lysis using the simulation model, the travel distances were positively corr elated to volume, or number of particles, and negative correlated to the sl ope angle, kinetic friction and rolling friction of particles when the init ial potential energies were the same. The mass of particles of equal size d id not affect the distance travelled. As the number of particles increased, the simulated travel distances tended to be longer compared with theoretic al travel distances calculated using the friction between particles and the slope. Consequently, we could determine the distance of the lumped mass mo del as being critical between fluidized and non-fluidized landslides. (C) 2 000 Elsevier Science B.V. All rights reserved.