Abstract
Earthquake observations of soft ground have been performed since 1990 in Tomakomai City, Hokkaido. And earthquake observations of a road embankment have been performed since 1996. Data have been recorded for 9 earthquakes. The seismic motions that were recorded have ranged from minor motions to motions strong enough to produce amplification in which the seismic behavior of soft ground and the road embankment is non-linear. This study uses these records to examine the nonlinear seismic behavior of a road embankment. The results show that the seismic behavior of soft ground and the road embankment is nonlinear, that a cross-sectional area of the embankment behaves as an integrated system, and that the low-order natural frequency is roughly the same in the ground as in the embankment.
