Impacts of Tidal Cycle and Level on the Erosion of Dispersive Soils - A Physical Model Study

Abstract

This study presents the effects of tidal cycle and level on the erosion of dispersive soils. A series of physical model tests simulating the tidal phenomenon, which leads to the soil seepage, were performed. There were four different soil types having different dispersion percentages used in the study. It was attempted to determine relationships among dispersion percentage (%D), number of tidal cycle (N_c) and mass of solid in suspension (M) at the design life. From the results of this study, the followings were found. With increasing N_c, the mass of soil particles eroded and transported by the seepage increased but with a decreasing rate. The rate became rather constant with the non-dispersion soils, but once again, rapidly increased with increasing N_c for the dispersive soil. When comparing at the same N_c, the soils with more %D value experienced more amount of particles eroded and transported by the seepage. The M value could be related with the %D and N_c as with the empirical formula proposed in this study.