PFC2D-based investigation on the mechanical behavior of anisotropic shale under Brazilian splitting containing two parallel cracks

doi:10.1007/s11707-021-0895-8

Frontiers of Earth Science

2021, Vol. 15

Issue (4): 803-816 https://doi.org/10.1007/s11707-021-0895-8

本期目录

PFC^2D-based investigation on the mechanical behavior of anisotropic shale under Brazilian splitting containing two parallel cracks

Bo HE^1,^2,³, Jun LIU^1,³, Peng ZHAO^2,³(

), Jingfeng WANG²

¹. Key Laboratory of Deep Underground Science and Engineering, Sichuan University, Chengdu 610065, China
². College of Architecture and Environment, Sichuan University, Chengdu 610065, China
³. Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China

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Abstract：

A validated particle flow code (PFC^2D)-based model was developed to investigate the indirect tensile mechanical behavior of shale containing two central parallel cracks under Brazilian splitting test conditions. The results show that preexisting cracks have a significant and insignificant influence on the tensile strength of shale under LPL and LVL conditions, respectively. When L≥10 mm, changing the L and H values has little effect on the tensile strength of shale. However, the inclusion of preexisting cracks have a positive effect on reducing the anisotropy of the shale specimens, and in the case of an L/D ratio of 0.3, the shale anisotropy is the lowest. Four failure modes were formed at different β and θ values under LPL conditions. In the case of β≥60°, the failure mode is mainly affected by β, and when β≤45°, the failure mode is more complicated than in the case of β≥60°. Only three major failure modes were observed under LVL conditions; in the case of 45°≤β≤75° and θ≤30°, the most complex failure mode occurred.

Key words： anisotropy preexisting cracks tensile strength mechanical behavior PFC^2D

收稿日期: 2020-01-04 出版日期: 2022-01-20

Corresponding Author(s): Peng ZHAO

引用本文:

. [J]. Frontiers of Earth Science, 2021, 15(4): 803-816.
Bo HE, Jun LIU, Peng ZHAO, Jingfeng WANG. PFC^2D-based investigation on the mechanical behavior of anisotropic shale under Brazilian splitting containing two parallel cracks. Front. Earth Sci., 2021, 15(4): 803-816.

链接本文:

https://academic.hep.com.cn/fesci/CN/10.1007/s11707-021-0895-8
https://academic.hep.com.cn/fesci/CN/Y2021/V15/I4/803

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