Mechanical behaviour of caisson foundations: insights from centrifuge tests
Mechanical behaviour of caisson foundations: insights from centrifuge tests
Caisson foundations are an efficient solution for offshore structures due to their installation simplicity and the possibility of reuse or controlled decommissioning. However, their mechanical behaviour still presents open challenges, such as the role of the soil enclosed within the caisson, the effect of installation on the stress state, the influence of soil foundation stiffness, and, more generally, the response under inclined and eccentric cyclic loads. Key design issues include the definition of failure conditions, the accumulation of permanent rotations under cyclic loading, and the interaction between vertical, horizontal and moment components, which remain only partially resolved despite past numerical and experimental studies.
To address these aspects, a centrifuge test campaign was carried out at TU Delft. Small-scale caisson models were tested in sand deposits prepared at controlled density and subjected to monotonic and cyclic inclined loading. Cyclic tests explored different load amplitudes and sequential stages, aiming to reproduce progressive deformation accumulation and the probabilistic nature of wind-induced actions.
Preliminary findings indicate that the ultimate capacity under eccentric loading is strongly influenced by the applied vertical load. The experimental results provide a valuable benchmark for the calibration of advanced numerical models and for the definition of interaction domains, supporting the development of simplified but reliable design tools for offshore geotechnical applications.
Gabriele Boccieri; R. Cesaro; R. Conti; Raffaele Di Laora; Luca Flessati; Pietro Marveggio; Gabriele Della Vecchia
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Session 6: Onshore and offshore foundation systems
https://doi.org/10.53243/ICPMG2026-409