パイピングにより堤体表面に現れる沈下分布の特徴

抄録

This paper presents results of centrifuge tests to study settlement profile of river levee slope due to loss of soil from the piping inside the levee. Relationship between settlement profile and size and location of piping holes is established, which makes it possible to identify the piping based only on settlement of slope surface. The possible piping holes of Kinugawa river levee, in which sand was ejected from levee toe during the flooding event in 2015, are estimated using the relation. At the same site, penetration tests are conducted to identify the locations where the soil loosened possibly by piping during the flooding. It was found that the location estimated by the relation coincided with that detected by the penetration tests, confirming the validity of the relationship.