Particle breakage in granular materials — a conceptual framework

Abstract

A simple, yet complete framework is introduced with the aim of modelling grain breakage in soils and crushable granular materials. The evolution of grain breakage is measured using a specific parameter of the grain-size distribution. The evolution of this new breakage parameter is related to the applied mechanical work, which allows the predictions to be independent of the stress paths. The correlation function proposed is trilinear, and is capable of describing the initiation, development, and stabilization of breakage. The initial state, coupled with three additional parameters, is used to calibrate this function. The three parameters are related to a grain specific quantity representing the strength of the particles that form the granular medium. The theory of fractal fragmentation is adopted, and the final state is considered to be unique and described by a single parameter: the fractal dimension. When tested against experimental results, this model was able to correctly predict the crushable behavior of a sand.

Weathered Granite Soils

“…Substituting M f = q f /p and M c = q c /p into Eqs. (7) and (8), respectively, gets the function of q f and q c as Eqs. (9) and (10) on the p-q plane, which are the exponential functions: Figure 21.…”

“…Furthermore, the particle breakage characteristics of soils are affected by the particle size distribution. The particle size distribution of in situ weathered granite soil has been paid little attention in previous studies, but it is very important to have a full understanding of the particle size distribution of in situ weathered granite soil, because the particle size distribution has considerable influences upon engineering properties of weathered granite soil such as compatibilities, permeabilities, and strength-deformation characteristics [4][5][6][7].…”

“…Given that wet conditions may influence the evolution of embankments after construction, future extensive research should be focused on dynamic measurement methods of particle breakage and long-term behavior degradation analysis of subgrade as a result of further weathering and particle breakage [7,11,30,31]. It is very difficult to entirely understand the road performance of weathered granite soil due to its special mechanical properties.…”

Numerical simulation of the effect of grain fragmentation on the evolution of microstructure quantities

“…The mechanisms of grain fragmentation are complex and various concepts for analysing experimental investigations and mathematical modelling are proposed in the literature, e.g., [2, 16, 20, 23, 24, 30, 43-45, 51, 53]. Experimental investigations reveal that the evolution of grain fragmentation strongly depends on the morphology of the granular material, the grain strength and the loading path, e.g., [3,18,32,39,[47][48][49][50].…”

Weathering Process of In Situ Granite and Particle Breakage Characteristics of Compacted Weathered Granite

“…Given that wet conditions may influence the evolution of embankments after construction, future extensive research should be focused on dynamic measurement methods of particle breakage and long-term behavior degradation analysis of subgrade as a result of further weathering and particle breakage [29][30][31]. Analyzing the weathering mechanism and particle breakage characteristics of rock by using fracture mechanics is still a challenging task, so researchers and engineers should pay more attention to the weathering mechanism of granite by means of fracture mechanics and micromechanics and evaluate the stability and safety of the subgrade filled with weathered granite by using safe rock theory in the future.…”