Soil Liquefaction due to Long Duration Earthquakes with Low Acceleration

Severe soil liquefaction due to a long duration earthquake with low acceleration occurred at Tokyo Bay area in the 2011 off the Pacific coast of Tohoku Earthquake. This phenomenon clearly shows that soil liquefaction is affected by properties of input waves. This paper describes effect of wave properties of earthquake on liquefaction using effective stress analysis with some earthquakes. Analytical result showed that almost the same pore water pressure was observed due to both a long duration earthquake with max acceleration of 150 gal and typical inland active fault earthquake with 891gal. Additionally, liquefaction potentials for each earthquake were evaluated by assessment of liquefaction potential with accumulated damage, which is used for design of railway structures in Japan. As a result, it was found that accurate liquefaction resistance on large cyclic area is necessary to evaluate liquefaction potential due to a long duration earthquake with low acceleration by assessment of liquefaction potential with accumulated damage.