摘要
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 differentβandθvalues under LPL conditions.In the case ofβ≥60°,the failure mode is mainly affected byβ,and whenβ≤45°,the failure mode is more complicated than in the case ofβ≥60°.Only three major failure modes were observed under LVL conditions;in the case of 45°≤β≤75°andθ≤30°,the most complex failure mode occurred.
基金
the financial support from the Science and Technology Department of Sichuan Province(Nos.2021YFH0048 and 2021YFH0118)
a project funded by the China Postdoctoral Science Foundation(No.2020M683253).