Soil Liquefaction Along the Tokyo Bay Coast Induced by the 2011 Off the Pacific Coast of Tohoku Earthquake

Abstract

The 2011 Off the Pacific coast of Tohoku earthquake resulted in widespread soil liquefaction along the coast of Tokyo Bay and the Tone River basin, causing extensive damage. This paper reports on cases of damage from soil liquefaction, with a primary focus on the results of investigations performed immediately after the earthquake (13th–17th of March) in mainly Urayasu City, Chiba Prefecture, the damage to detached houses implemented soil cement columns, and the restoration methods of tilting detached houses. Predominant features of liquefaction damage include (1) a long duration of ground motion, (2) expanded liquefaction damage during aftershocks, (3) liquefaction of low-plasticity silt (dredged silt in particular), (4) sinkage and tilting of a majority of detached houses, and (5) an extended period of water and sewage service stoppage. The damage to detached houses complemented soil cement columns depending on the depth of the soil cement column base and the filling soil layer.