Fluidization in cemented and uncemented granular soils with application to suction-assisted bucket embedment

¹ INRAE, Aix Marseille Univ., RECOVER, 3275 Route Cézanne, Aix-en-Provence, 13100, France
² BAM, Federal Institute for Materials Research and Testing, Berlin, Germany
³ Referat 62 (Dams and Hydraulic constructions), Bayerisches Landesamt für Umwelt, Bürgermeister-Ulrich-Straße 160, Augsburg, 86179, Bavaria, Germany

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 1 December 2025

Abstract

Internal hydraulic flows in granular soils are known for their ability to partially or totally fluidize the material, thus causing a significant loss of mechanical strength. Although this effect is generally undesirable, it can be exploited in certain situations, in particular to facilitate the penetration and anchoring of a bucket-shaped foundation structure in the ground by controlled suction. This type of operation is, however, delicate, with the main risk being the formation of a localized fluidization zone (a phenomenon often called piping or rat-holing) which stops any further penetration of the bucket and may pose a risk to the structure integrity. Using a small-scale physical model built to qualitatively reproduce installation scenarios of foundations for offshore wind turbines, systematic experiments have made it possible to analyze the mechanism of a cylindrical bucket embedment under the effect of suction. Two different types of artificial granular soil are considered: glass beads with and without cementation by solid paraffin bonds. We present here a summary of the results obtained in terms of critical embedment conditions (pressure drop, flow rate) and embedment kinetics (final depth).