Robert Spears

Lattice Formation in Liquefaction: a Study Using Numerically Evaluated Particle Dynamics Robert Spears

Liquefaction is the loss of shear resistance in a soil under various loading conditions. It is an important topic of study in seismic engineering due to its potential to cause damage to structures that otherwise could survive a seismic event. In liquefaction, the movement of particles is generally viewed as random and isotropic. A numerical study has been performed based on the hypothesis that as liquefaction occurs, initially randomly placed particles become organized into a lattice structure. As a result, the initial behavior may be isotropic, but there is a progressive movement to anisotropic behavior as cyclic shearing is applied. The study is performed under ideal conditions considering spherically shaped particles of the same size in pure shear. The results of the study showed that the particles organize to the same lattice structure regardless of friction coefficient or shear plane selection. Consequently, this study provides a tool for calibrating constitutive models related to liquefaction. It also provides an accurate discrete element method for evaluating particle dynamics.