One-dimensional compression feature and particle crushability behavior of dry calcareous sand considering fine-grained soil content and relative compaction

The particle breakage of porous and angular calcareous sand (CS) at the high-stress level is essential on compression feature but less quantified. In this research, a series of compression experiments and laser particle size analyzer tests were conducted under different ending pressures considering relative compaction and fine-grained soil (FS) content to investigate compression behavior and particle breakage of CS. The results indicate that the rebound curves are almost horizontal with a rebound index are between 0.0021 and 0.0054, and the FS content (smaller than 10%) has a little impact on resilience behavior. The irreversible plastic deformation is the main part of compression deformation. Besides, there exist two pressure thresholds of 400 kPa and 100 kPa corresponding to void ratio change trend when FS contents are smaller than 10% and reach 10%, respectively. Moreover, with FS contents increase from 0 to 10%, the moving distance of grading curves to the right becomes shorter gradually which suggests that the quantities of particle crushability decrease. FS can relieve stress concentration among CS that leading to less particle crushability. The combination of these factors including FS content, relative compaction, and axial loading has a complex effect on the relative crushability ratio. Both FS content and relative compaction can restrain particle crushability while axial loading could promote particle crushing. In addition, the relative crushability ratio has a negative linear relation with FS content and relative compaction. But, the relation between particle crushability ratios with axial loading can be described as a logarithmic function well. However, when relative compaction increases to a certain degree of 0.7, the influence of pressure on the relative crushability ratio is weakened. Similarly, the effect of relative compaction on the void ratio is weakened when the FS content is increased. Furthermore, there is a good negative linear correlation between the void ratio and relative crushability ratio.