Evolution of particle breakage and volumetric deformation of binary granular soils under impact load

Binary granular soils, mixtures of carbonate sands and nonplastic fines, are widely used for constructions of foundation, airport and embankment in island and coast. Impact load (e.g., sea wave, aircraft landing, pile driving and dynamic compaction during foundation, et al.) is frequently exerted to the mixtures. It is therefore of extreme importance to investigate the evolutions of particle size distribution, particle breakage and volumetric deformation of the mixtures under impact load due to that the grains of carbonate sands are easily to be crushed, which may significant affect its mechanical behavior. Three mixtures (i.e., 100% carbonate plus 0% fines (by dry weight), 90% carbonate plus 10% fines and 80% carbonate plus 20% fines) were prepared to analyze the effect of fines content on particle breakage and volumetric deformation under impact load. It was observed that a unique fractal grading could be obtained for all the mixtures when the blow number was large enough (N>20,000\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N>20,000$$\end{document}). The void ratio of the mixtures converged to be a constant ultimate value as the mixture reached the fractal state. The volumetric strain and relative particle breakage with respect to the blow number could be described by hyperbolic functions, indicating that the volumetric strain and relative particle breakage progressively increased to ultimate values with increasing the blow number.