One method of improving soil so that liquefaction-related ground failure is reduced is called dynamic deep compaction. Dynamic deep compaction involves repeated dropping of a large weights(as much as 10 to 40 tons)from heights up to 200 to 300 feet (Mitchell and Wentz, 1998). Note the holes in the foreground made by weight drops. This process densifies the soil, making it less susceptible to liquefaction. This method is probably not appropriate in areas with nearby structures...(Photograph from Mitchell and Wentz, 1998)

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