International Session (Geotechnical Engineering)

[CS2-02] EFFECTS OF EROSION ON THE MECHANICAL PROPERTIES OF WELL-GRADED VOLCANIC SOIL

〇Chitravel Sanjei¹, Sho Kubota², Reiko Kuwano¹, Masahide Otsubo¹ (1.The University of Tokyo, 2.Hokkaido University)

Keywords:Well-graded, Suffusion, Erosion-triaxial, Undrained, Monotonic loading

Internal erosion can be divided into four types: concentrated leak erosion, contact erosion, backward erosion and suffusion. Out of them, suffusion is characterized as seepage induced loss of fine particles with no change in volume and an increase of hydraulic conductivity. The degree of migration of fine particles can affect both micro and macro structural behaviour of soil. This paper analyses the impacts of suffusion on the mechanical properties of well graded volcanic soil with different relative densities of 80%, 50% and 30% in triaxial compression. It was observed that looser eroded soil become stiffer while medium dense and denser soils become less stiff or unchanged.