Grain crushing in geoscience materials: Key issues on crushing measure, testing and modelling: Review and Preface
Grain crushing is commonly encountered in deep foundation engineering, high rockfill dam engineering, railway engineering, mining engineering, coastal engineering, petroleum engineering, geoscience, etc. Grain crushing is fundamentally affected by the internal factors, e.g., mineral strength, grain size, grain shape, grading, density and specimen size, and also by the external factors, e.g., stress level, stress path, loading rate, loading time, saturation condition, temperature and acidic erosion. Crushable material becomes a series of different materials with the change in its grading during grain crushing, resulting in a great decrease in strength and dilatancy and a sharp increase in deformation of specimens composed of crushable material, and further leading to failure of structure in geoengineering and geoscience. Effects of grain crushing on strength, dilatancy, deformation and failure mechanisms have been extensively investigated through laboratory testing, discrete element method (DEM) modelling, Weibull statistics, and constitutive modelling within the framework of the extended crushing-dependent critical state theory or the energy-based theory. Eleven papers summarized in this review article for this special issue addressed the above issues in grain crushing through the advanced testing and modelling.
Keywords: Grain crushing, Particle breakage, Strength, dilatancy, DEM modelling, Constitutive modelling