Mathematical model revealing the evolution of particle breakage and particle-size distribution for rockfill during triaxial shearing

Abstract

A mathematical model reflecting the evolution of both particle breakage and particle-size distribution (PSD) for rockfill subjected to triaxial shear has been proposed in this article. First, the PSD of a soil is expressed by a gradation equation which has been shown to be widely applicable by comparison with a large amount of test data from soils encountered in practice. Then two particle breakage factors B_g and B_r are suggested and proved to be two suitable breakage factors in the model. Mathematical relationships between B_g, B_r and the gradation equation’s parameters b and m are derived. Then, correlations between the two breakage factors, effective mean normal stress and generalised shear strain during shearing are expressed by empirical functions, with several drained triaxial compression test data verifying the applicability. The inter-relationships of particle breakage, PSD and stress state of rockfill are thereby established, providing what is termed the PSD evolution model. Additionally, the proposed PSD evolution model is verified by successfully predicting the particle breakage factors and PSDs of rockfill triaxial specimens.

Keywords:

• Rockfill
• particle breakage
• particle-size distribution
• evolution model
• gradation equation

Acknowledgements

The authors gratefully acknowledge the research grant (GG201705) from Key Technologies R&D Program of Henan water conservancy, fund on basic scientific research project of nonprofit central research institutions (Y318005).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research grant (GG201705) from Key Technologies R&D Program of Henan water conservancy, fund on basic scientific research project of nonprofit central research institutions (Y318005).