Micromechanics of Liquefaction in Granular Materials

Soil liquefaction is a poorly understood phenomenon, yet it can be critical in civil engineering: Relative displacement of soil grains under deformation can destroy the grain-contact fabric, and if the grains then become suspended in interstitial water, the soil behaves like a liquid, unable to sustain any load. The authors create a micromechanical model to simulate grain dynamics at the pore scale in the presence of water, successfully reproducing the behavior observed during liquefaction. Interestingly, the number of contacts between grains prior to deformation acts as a critical state variable in determining the occurrence of liquefaction.