Discrete element numerical analysis for bearing characteristics of coral sand foundation considering particle breakage

Owing to the construction demands of island and reef engineering, studying the bearing and deformation characteristics of coral sand foundations is significant. This study used the discrete element method to simulate the plate loading test of coral sand foundations based on the actual experiments of coral sand foundations. The particle breakage of coral sand was considered by the fragment replacement method, and the influence of relative compactness on the particle breakage behaviour and compression deformation characteristics of coral sand foundations was analysed. The results show that the compression process of the coral sand foundation undergoes three stages: compaction, shear deformation, and failure. The bearing capacity, deformation modulus, and particle breakage rate of the coral sand foundation increase with the increasing relative compactness, but the growth trends are different significantly at different relative compactness. The numerical analysis indicates when the relative compactness of the foundation increases, the contact force and coordination number would increase, the relative displacement would decrease, causing more particle breakage. This microscopic phenomenon explains why the increasing trend of bearing capacity and deformation modulus of the foundation decreases with the increasing relative compactness.