Reports of damage to embankments from earthquakes are frequent, but the state of the damage is likely to vary depending on the conditions in the embankment and in the foundation beneath. With this in mind, a numerical analytic investigation was conducted of differences in seismic and post-seismic deformation behavior depending on initial variations in the firmness (density) of the foundation and embankment.

The results showed that: ① where the foundation and embankment were both firm, stability was maintained both during and after the quake, with only small amounts of deformation; ② where the foundation was firm but the embankment soft, there was a concentration of deformation in the embankment, resulting in considerable lateral swelling; ③ where the embankment was firm but the foundation soft, stability was preserved during the quake, but damage from circular slip occurred afterwards.

1. Noda, A., Nakai, K. and Asaoka, A. (2008): Consolidation of clay and compaction/liquefaction of sand – A structure theoretic approach -, Theoretical and Applied Mechanics JAPAN, Vol.57, pp.41-47.