Lattice Formation in Liquefaction

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.