Experimental Evaluation of Crushed Stone Backfill Reaction Behind Concrete Caissons Under Cyclic Loading
Experimental Evaluation of Crushed Stone Backfill Reaction Behind Concrete Caissons Under Cyclic Loading
Concrete caisson structures founded on crushed stone mounds are widely used in Japan and have increasingly gained international recognition as effective coastal wave defence systems. However, recent damage caused by high waves and tsunamis has prompted renewed efforts to reinforce these structures. A commonly adopted reinforcement measure involves placing a crushed stone reinforcing embankment behind the caisson, which improves resistance against sliding, bearing capacity failure, and excessive toe pressure. Despite these developments, the overturning resistance of caissons remains insufficiently understood, mainly due to the limited knowledge of resistance mobilisation in crushed stone embankments under small rotational displacements and cyclic movements of the caisson. This study investigates the fundamental resistance characteristics of crushed stone reinforcing embankments against caisson rotation through centrifuge model tests using an inclined loading plate. The model test results demonstrate a distinctly nonlinear relationship between resistance force and inclination angle, with resistance behaviour strongly influenced by cyclic loading history. Under monotonic loading, the resisting moment increased with inclination angle, indicating that resistance continued to be mobilized at large rotations. In contrast, after exposure to large rotational loading, the resistance against smaller subsequent rotations decreased. These results highlight the importance of accounting for nonlinear and cyclic resistance characteristics when evaluating overturning stability of reinforced caisson structures.
O. Kurihara; Hidenori Takahashi
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Session 3: Resilient geotechnical infrastructure
https://doi.org/10.53243/ICPMG2026-34