How does liquefaction occur?

Answer 1

Liquefaction is the condensation of a gas. It is the process of turning a gas into a liquid.

Answer 2

Liquefaction is the process of liquefying or making liquid.(as told by dictionary.) Liquefaction is the process where soil loses strength and acts like a liquid instead of a solid.

Please see the related question for an explanation of the cause of liquefaction.
Did you mean liquefaction?

1) Liquefaction:

It means the change from any state of matter (except already liquid) to liquid. Or the turning of something into a liquid state.

2) The process of making synthetic liquid fuel from coal.

For other senses see the link bellow.

Answer 3

Liquefaction occurs in cohesionless soils (typically those with a higher content of larger grains such as sand sized clasts) which have water in the pore spaces, and are poorly drained.

When the seismic waves from the earthquake pass through the soil, the vibrations cause the individual grains in the soil to move around and re-adjust their positions. This ultimately results in a decrease in volume of the soil mass as the grains pack more tightly together (a reduction in porosity).

The pore water which was originally in those spaces becomes compressed. Water is relatively incompressible and as such it pushes back against the soil grains (more correctly this is described as an increase in pore water pressure). The pore pressure becomes so high, that the soil grains become almost buoyant causing a significant drop in the shear strength of the soil to a very low value.

When this occurs the soil loses it's ability to support loads (technically described as a loss of bearing capacity) which can cause subsidence of building foundations.
Liquefaction occurs when water-laden sand or silt is subject to vibration such that the water will now escape, also carrying with it, some of the finer silts and sands.

Also known in seismology circles as Sand Volcanoes where appropriate.

Addition. To minimise liquefaction, one successful approach id to lower into the ground, a self digging apparatus till the desired depth is reached; then it is set in motion vibrating the soil surrounding it. This consolidates the sediment layer itself, and de-waters it up to the surface.

The ground surface will naturally alter during this process, and the surface is graded to the desired contours, filled as necessary with overburden, and smoothed off.

The equipment used at Pegasus Town north of Christchurch New Zealand, originated from Bahrein, where presumably this is the technique used to create the 'sand islands'.

Answer 4

Liquefaction occurs when saturated soil loses its strength due to increased pore water pressure during an earthquake or other rapid loading event. This causes the soil to behave like a liquid, leading to ground failure, settlement, and potentially damaging structures built on top of it.