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.

开发了一个经过验证的基于粒子流代码 (PFC ^2D ) 的模型，以研究在巴西劈裂试验条件下包含两个中心平行裂缝的页岩的间接拉伸力学行为。结果表明，在LPL和LVL条件下，预存裂缝对页岩抗拉强度的影响分别显着和不显着。当L ⩾ 10 mm 时，改变L和H值对页岩的抗拉强度影响不大。但是，包含先有裂缝对降低页岩试样的各向异性有积极作用，在L/D比为0.3的情况下，页岩各向异性最低。四种失效模式形成于不同LPL 条件下的β和θ值。在的情况下，β ⩾60°，故障模式主要受β，并且当β ⩽45°，故障模式被不止在的情况下复杂β ⩾60°。在 LVL 条件下仅观察到三种主要故障模式；在45的情况下°⩽ β ⩽75°和θ ⩽30°，发生最复杂的故障模式。