Soil liquefaction

Manhole surface floated due to soil liquefaction

Soil liquefaction is a process by which the soil behaves not as a solid , but as a dense fluid ( fluid ). Liquefaction ^{[1] is} more characteristic of moisture-saturated bulk soils, such as silty sands or sands containing intercalations of water-tight sediments ^[2] .

The rocks most prone to liquefaction are relatively young ( Holocene ), these are sands and silts with particles of the same size, at least a meter thick and saturated with water . Such rocks are often found along the river beds, off the coast, where loess and sand have accumulated. Some examples of liquefaction are: quicksand , quartz clay , turbid flux and seismic liquefaction.

Dilution of the soil can occur during an earthquake , because with the passage of a seismic wave, soil particles begin to oscillate at different speeds and some of the contact between them breaks, as a result the soil can become water with grains suspended in it. Water tends to be wrung out, but before the ground returns to its original state, the buildings standing on it can be destroyed. Severe destruction caused by the liquefaction of soils, occurred in 1964 : March 27 off the coast of Alaska near Anchorage and June 16 in Niigata ^[3] . Liquefaction mainly occurs in lowlands, on the sea coasts, near rivers, lakes and bays. For example, in California , where seismic activity is high in the area of the San Andreas Fault and other places, areas of the coast of the San Francisco Bay , the coast of the Pacific Ocean and the neighborhood of Los Angeles are liquefied. Three methods are used to reduce the risk of dilution: vibroflotation (vibration with simultaneous introduction of water), drainage (removal of water from the reservoir) and removal of the reservoir itself, which is likely to liquefy ^[4] .