Effect of local non-convexity on the critical shear strength of granular materials determined via the discrete element method--颗粒学报PARTICUOLOGY

Nie, Z., Liu, S., Hu, W., & Gong, J. (2020). Effect of local non-convexity on the critical shear strength of granular materials determined via the discrete element method. Particuology, 52, 105-112. https://doi.org/10.1016/j.partic.2019.12.008

Effect of local non-convexity on the critical shear strength of granular materials determined via the discrete element method

Zhihong Nie ^a, Shunkai Liu ^a, Wei Hu ^b, Jian Gong ^c *

a School of Civil Engineering, Central South University, Changsha, Hunan 410075, China
b Hunan Province Key Laboratory of Geotechnical Engineering Stability Control and Health Monitoring, Hunan University of Science and Technology, Xiangtan, Hunan 411201, China
c School of Hydraulic Engineering, Changsha University of Science and Technology, Changsha 410114, China

10.1016/j.partic.2019.12.008

Volume 52, October 2020, Pages 105-112

Received 22 May 2019, Revised 16 October 2019, Accepted 19 December 2019, Available online 3 February 2020, Version of Record 24 June 2020.

E-mail: gj_csu@hotmail.com

Highlights

• Effect of local nonconvexity on the residual shear strength of granular matter is studied.

• Contributions of certain contact types to the residual shear strength are analyzed.

• Effect of local nonconvexity on fabric anisotropy is evaluated.

Abstract

Multi-sphere clumps are commonly used to simulate non-spherical particles in discrete element method simulations. It is of interest whether the degree of local non-convexity λ affects the mechanical behaviour of granular materials with the same non-convexity η. A series of discrete-element-method biaxial shear tests are conducted on rough particle packings with η = 0.075 and different λ values (ranging from 0.134 to 0.770). The microscale results show that the contact type changes with an increase in λ. However, the critical strength is independent of λ. The evaluation of the contributions of different contact types to the critical shear strength and a detailed analysis of the anisotropies help clarify the microscopic mechanisms that result in the independence of the critical shear strength from λ.

Graphical abstract

Keywords

Multi-sphere clump; Local non-convexity; Discrete element method; Biaxial shear test; Contact type; Critical shear strength

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