Effects of cyclic traffic loads and seawater erosion on suffusion of crushed calcareous sands

Calcareous sands, in contrast to ordinary terrestrial source sands, are characterized by their propensity for fragmentation. This leads to the fracturing of calcareous sands within the foundation under the impact of traffic loads. The crushed calcareous sands then experience suffusion due to cyclic wave action, potentially causing foundation settlement. However, limited research has been conducted on the effects of varying load frequencies and magnitudes on road foundations subjected to cyclic traffic loads. In this study, a series of numerical case studies employing the CFD-DEM method are conducted. The macroscopic and microscopic effects of load magnitude and frequency on fines loss mass, fines loss rate, soil surface displacement, and microstructure are analyzed. The results indicate that as the traffic load magnitude increases and frequency decreases, fines loss mass and volumetric strain of the soil decrease, reducing the suffusion effect on the foundation. These findings provide valuable insights for the development of micromechanical constitutive models for calcareous sands and the design of transportation infrastructure.