TY - JOUR
T1 - DEM modeling of large-scale triaxial test of rock clasts considering realistic particle shapes and flexible membrane boundary
AU - Zhang, Junqi
AU - Wang, Xiang
AU - Yin, Zhen Yu
AU - Liang, Zhengyu
N1 - Funding Information:
Our deepest gratitude goes to the editors and two anonymous reviewers for their careful work and thoughtful suggestions. The constructive comments are helpful to enhance the contents and the presentation of this paper. Moreover, this research is supported by the Doctoral Fund of Central South University (No.: 1053320170862 ), the Research Grants Council (RGC) of Hong Kong Special Administrative Region Government (HKSARG) of China (Grant No.: 15209119 ). The authors would like to express appreciation for the financial assistance.
Publisher Copyright:
© 2020 Elsevier B.V.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/12/20
Y1 - 2020/12/20
N2 - This paper presents a novel framework for the discrete modeling of the large-scale triaxial test of rock clasts, considering both the realistic particle shapes and veritable flexible boundary condition. First, real-shaped particle models for the tested rock clasts are precisely reconstructed using the close-range photogrammetry technique. The rubber membrane was modeled by a series of bonded particles. Then, the laboratory procedures of the triaxial test, i.e., sample preparation, isotropic compression, and shearing, are reproduced in the DEM simulations with consideration of the veritable confining boundary. To ensure more reliable numerical results, a systematic DEM calibration framework is established to determine the modeling parameters based on a series of calibration experiments, including tensile test, suspension test, clast-membrane sliding test, and large-scale triaxial test. Finally, the proposed method is applied to investigate the effects of confining pressure on the macro- and micro-mechanical behaviors of rock clasts. The presented works lay a foundation for further studies on revealing the mechanisms of the conventional triaxial test, e.g., the effect of end restraint and rubber membrane. Moreover, the proposed systematic framework for calibration of modeling parameters can be applied to precisely capture the real mechanical properties of various types of granular rock-like materials in DEM simulations.
AB - This paper presents a novel framework for the discrete modeling of the large-scale triaxial test of rock clasts, considering both the realistic particle shapes and veritable flexible boundary condition. First, real-shaped particle models for the tested rock clasts are precisely reconstructed using the close-range photogrammetry technique. The rubber membrane was modeled by a series of bonded particles. Then, the laboratory procedures of the triaxial test, i.e., sample preparation, isotropic compression, and shearing, are reproduced in the DEM simulations with consideration of the veritable confining boundary. To ensure more reliable numerical results, a systematic DEM calibration framework is established to determine the modeling parameters based on a series of calibration experiments, including tensile test, suspension test, clast-membrane sliding test, and large-scale triaxial test. Finally, the proposed method is applied to investigate the effects of confining pressure on the macro- and micro-mechanical behaviors of rock clasts. The presented works lay a foundation for further studies on revealing the mechanisms of the conventional triaxial test, e.g., the effect of end restraint and rubber membrane. Moreover, the proposed systematic framework for calibration of modeling parameters can be applied to precisely capture the real mechanical properties of various types of granular rock-like materials in DEM simulations.
KW - Calibration
KW - Discrete element method
KW - Flexible membrane
KW - Particle shape
KW - Rock clast
KW - Triaxial test
UR - http://www.scopus.com/inward/record.url?scp=85096187479&partnerID=8YFLogxK
U2 - 10.1016/j.enggeo.2020.105871
DO - 10.1016/j.enggeo.2020.105871
M3 - Journal article
AN - SCOPUS:85096187479
SN - 0013-7952
VL - 279
JO - Engineering Geology
JF - Engineering Geology
M1 - 105871
ER -