Abstract
Soil movement in seabed induced by ocean wave is caused with complex interaction between traction force and effective stress change due to seepage force. This study investigated the soil movement phenomena under various soil density condition that focused on the influence of the Shields number and the excess pore water pressure ratio by using wave flume experiment device. PIV analysis was also done to quantitatively evaluate soil movement. In the case of loose density of soil, liquefaction occurred with the phase difference of the pore water pressure fluctuation and the accumulation by residual pore water pressure. The soil particles showed the elliptic movement similar to water particles. On the other hand, in the case of medium-dense soil, the soil was moved to offshore direction due to flow velocity in the ground surface when the effective stress decreased near the surface layer due to the phase difference of the pore water pressure fluctuation. In addition, we found that not only movement of soil particles but also fluctuation in layer units by the PIV analysis.
