Soil liquefaction

Soil liquefaction can take place by an earthquake due to strong shocks hydrous sandy soil layers. Particularly fine sandy layers with low water permeability ( permeability ) are at risk. Here, a on all sides of propagated pressure ( dynamic load ) is applied to the non-compressible water between the sand grains that had a solid structure until then. A flow pressure gradient, also called excess pore water pressure builds up in the sand layer. In this case, the grain structure is compressed and loses its shear strength, the sand layer liquefied into a sand - water slurry, areas of the surface can then be pressed out. The entire background layer is thus unstable, it constructed buildings sink. A harmless experiment can be carried out in the mud or on wet sand beach, when the wet sand on the occurrence does well around the foot.