Particle size composition of migrating soil particles and the time change in water-passing experiments for reproducing suffusion using turbidity

Abstract

The suffusion phenomenon that occurs in embankment structures, such as river levees and reservoir dams, may reduce the stability of the entire structures and can be a factor of aging. However, the transfer mechanism of soil particles through the gaps is unclear, and how suffusion progresses has not been sufficiently clarified. In this study, a one-dimensional water-passing experiment was performed, using a column device that enables the outflow of particles, to examine the time change of the particle size composition of discharged soil particles during the process of suffusion. The relationship between the amount and the size of the discharged soil particles was also examined. As a result, by inferring the particle size composition of the discharged soil particles from the relationship between the concentration and the turbidity of the drainage, it was clarified that the particle size composition of the discharged soil particles changed during the process of suffusion. Moreover, it was confirmed that, as more soil particles were discharged under highly saturated conditions, larger particles were discharged.