2025 Volume 67 Issue 2 Pages 167-181
Many cases of damage due to seepage at embankments and weirs are considered to be caused by piping phenomena that occur at strata boundaries and other areas with large permeability gaps. It is important in river structure management and geotechnical engineering to understand how the triggering water channel develops and leads to piping. In this paper, the mechanism of water channel development in the piping phenomenon was investigated by conducting seepage experiments on a sheet pile and a multi-layered embankment using the refractive index matching method. The visualization of the ground interior, which has been difficult to visualize so far, was performed with high accuracy, and the behavior of particles in the ground was traced to show the fluid behavior inside the water channel from the slight deformation of the ground during the piping phenomenon.
