Liquefaction

Definition

Liquefaction is a term used to describe the loss of soil strength and/or stiffness due to the generation of porewater pressure in saturated soil subjected to rapid loading. Liquefaction is most commonly triggered by earthquake ground shaking, but may also be caused by non-seismic loading (e.g., train traffic, rapid deposition of sediment, or construction vibrations).

Damage

Liquefaction has caused extensive damage in many historical earthquakes. Liquefaction damage is usually caused by the excessive ground deformations that result from the weakening and/or softening of liquefied soil. Liquefaction is frequently accompanied by the development of sand boils, small to large piles of ejecta brought to the ground surface by pressurized groundwater. Extensive weakening due to porewater pressure generation can cause soils that were stable prior to earthquake shaking to become unstable. When such soils support a building (Figure 1) significant weakening can cause foundation...