Remember that when liquefaction ends, the redeposited sand will be packed more densely around you.Get rid of extra weight like backpacks that make you sink more. Relax: The more you struggle, the more fluid the quicksand will become, and the faster you will sink.How can you escape it? Quicksand forms when water-saturated sand is agitated, breaking down frictional forces so that it is no longer able to support weight.The sand rapidly separates from the water and is redeposited as denser, more viscous sediment, trapping victims in newly reorganized tightly packed sand.The more stress, the more fluidized quicksand becomes. The sand becomes “quick” when motion, loading, vibration or upward migration of water breaks down the friction that holds the grains in place.If gently placed on quicksand, even dense materials will rest on the surface.The volume of water-filled void space is often greater than the volume of grains. Normal sand is packed together with about 25-30% of void space between the grains, but in quicksand, grains are more loosely packed with 30-70% porosity.Desert quicksand (with air-filled voids) may occur on the downwind side of dunes, but usually only a couple inches of sinking occurs in these cases, as the air is quickly expelled when the sand compacts under a load or vibration.Quick conditions may occur on beaches and tidal flats during low tides as the retreating sea leaves behind saturated sand.The force of shaking during earthquakes may increase groundwater pore pressure and trigger liquefaction of surface sand or silt, causing building foundations to shift.Natural springs can cause quick conditions to occur in alluvial fans or along riverbanks.It is a “shear thinning non-Newtonian fluid,” meaning that when undisturbed, the hydrogel looks solid, but just 1% change in stress will cause a sudden decrease in viscosity, or fluidization. ![]()
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