2006 Volume 42 Issue 6 Pages 457-466
The effect of geotopology on seismic motion was investigated in order to understand the characteristics of seismic motion that triggered landslides on mountains during the Mid-Niigata Prefecture Earthquake in 2004. Three-dimensional models were made of two mountains where large-scale landslides occurred, and seismic response analysis of these models was carried out by elastoplasticity FEM. This analysis revealed the following characteristics: 1) The amplification of seismic acceleration depended on the size and shape of the mountain. 2) Both surface soil and geotopology affected the seismic motion distribution in the mountain. 3) A comparison of the strain on the ground derived from the seismic response analysis with the landslide distribution revealed that the landslide sources were located in places where the strain on the ground was large
