Centrifugal Modelling of Underwater Stone Descent and Deposition

Publication Title
Centrifugal Modelling of Underwater Stone Descent and Deposition

Abstract

Foundation mounds composed of crushed stone with particle diameters ranging from several tens of centimetres to approximately one metre are widely utilised as subaqueous structural bases in coastal infrastructure, including breakwaters, quay walls, and seawalls. In gravity-type configurations, these mounds are directly emplaced upon the seabed, serving as critical load-bearing foundations for the superstructure. Conventional construction practices typically involve the release of crushed stone from dredger or barge vessels, resulting in deposits formed without underwater compaction, primarily due to the prohibitive cost of such operations. Despite their widespread application, the mechanical stability and deformation characteristics of these mounds remain insufficiently elucidated, particularly in relation to deposition parameters such as initial relative density. The present study seeks to advance understanding of these aspects through underwater drop tests conducted within a centrifugal field, with the objective of evaluating the descent trajectories and resultant packing states of the deposited crushed stone. Prior to testing, similitude laws governing stonefluid interactions were rigorously examined to ensure appropriate scaling of the experimental model. The findings reveal that the descent behaviour of crushed stone under terrestrial gravity (1g) or in air diverges significantly from that observed under centrifugal acceleration, with the latter condition yielding deposits of intermediate relative density.

Authors
Hidenori Takahashi; O. Kurihara

Published In

11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)

Theme

Session 6: Onshore and offshore foundation systems