NEW DEVELOPMENTS RELATED TO CLARIFICATION OF THE MECHANISMS OF GROUND DEFORMATION CAUSED BY EARTHQUAKES —IN THE WAKE OF THE GREAT EAST JAPAN EARTHQUAKE—

Abstract

The 2011 Great East Japan Earthquake caused massive ground damage, including liquefaction of sandy grounds, collapse of river levees and lands developed for housing, etc., particularly in regions across eastern Japan. Not only damage to "currently unqualified" structures that did not conform to existing design standards and codes but also ground damage that could not be explained within the framework of conventional geomechanics and geotechnical engineering was observed. Particularly in the latter case, therefore, it has become necessary to develop new techniques in geomechanics without being restrained by the conventional framework. From the above standpoint, this paper reviews the research that has been carried out in the field of geotechnology after the Great East Japan Earthquake. More specifically, new knowledge relating to the mechanism of liquefaction damage at Urayasu City and other ground deformation caused by the earthquake is introduced, together with the results of research carried out on ground strengthening techniques.

Land subsidence caused by seasonal groundwater level fluctuations in Kawajima (Japan) and one-dimensional numerical modeling with an evolutionary algorithm

“…This could have a negative impact on the model's predictive performance in predicting long-term subsidence. The possibility that strong seismic activity from the Tohoku Earthquake affected the secondary consolidation of the Holocene has been noted by several studies (Imakiire and Koarai 2012;Yasuhara and Kazama 2015;Noda et al 2017). Model A is likely to have been affected by the Tohoku Earthquake, and seismic effects on land subsidence modeling require further investigation.…”