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Earthquakes can cause soil liquefaction where loosely packed, water-logged sediments come loose from the intense shaking of the earthquake. The United State Geological Survey (USGS) creates liquefaction susceptibilty maps to help the general public as well as land-use planners, utilities and lifeline owners, and emergency response officials assess their risk from liquefaction.
The term liquefaction is commonly misapplied to the displaced, saturated sediment as opposed to the process by which it was formed.
The George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) hosts two geotechnical centrifuges for studying soil behavior. The NEES centrifuge at University of California Davis has radius of 9.1 m (to bucket floor), maximum payload mass of 4500 kg, and available bucket area of 4.0 m2. The centrifuge is capable of producing 75g's of centrifugal acceleration at its effective radius of 8.5 m. The centrifuge capacity in terms of the maximum acceleration multiplied by the maximum payload is 53 g x 4500 kg = 240 g-tonnes. The NEES centrifuge at the Center for Earthquake Engineering Simulation (CEES) at Rensselaer Polytechnic Institute has a nominal radius, 2.7 m, which is the distance between the center of payload and the centrifuge axis. The space available for the payload is a depth of 1,000 mm, width of 1,000 mm, height of 800 mm, and a maximum height of 1,200 mm. The performance envelope is 160 g, 1.5 tons, and 150 g-tons (product of payload weight times g).