Fracturing and Ultimate State of Binary Carbonate Sands

Abstract

Carbonate sand has been widely used as the building materials for land reclamation in marine areas in the recent decades. The complex inner structures and particle characteristics of carbonate sand increase the difficulty and complexity in foundation treatment. In this study, the particle breakage and ultimate state of binary carbonate sands with different small-grain contents and size ratios were investigated through impact loading tests. The results showed that the particle breakage and ultimate state are influenced by the small-grain content and size ratio. The breakage of the carbonate sands shows significant differences for different small-grain contents due to the fabric state varies between a coarse-sand-dominated state and a finer-sand-dominated state except for the size ratio of 1.92 where the effect of small-grain content is negligible. A hyperbolic function was proposed to establish the relationship between the input work and particle breakage. The evolution of the particle size distribution of the sand with the size ratio of 1.92 under impact loading follows a monofractal pattern as the uniformly graded soil behaves. The multifractal or bimodal phenomenon becomes more obvious when the size ratio increases. The particle shape, size effect, and coordination number on the fabric of the binary carbonate sand could affect the particle breakage and ultimate state of the specimens.