Abstract A hydro-mechanical coupled lattice-based model for the simulation of crack propagation induced by fluid injection in porous saturated rocks containing cohesive joints is presented. Rock follows an isotropic damage model for tensile fracture and cohesive joints follow a coupled plasticity-damage model. The discretisation uses a dual lattice approach: a Delaunay triangulation for the solid and the boundaries of the associated Voronoi tesselation for the hydraulic part. A classical poromechanical framework for a materials saturated with a single fluid is implemented. First, predictions of crack propagation are compared with analytical models. Then, the interaction between a propagating crack and an existing joint is analysed. Two configurations are considered: the case of a joint that is orthogonal to the crack path and the case of a joint that is inclined by 45 o with respect to the crack path. For the vertical joint, the crack is first arrested because the cohesive joint is weaker than the rock mass. The crack reinitiates at both crack tips and subsequently propagates in one of them. For the inclined joint, the crack follows the joint and therefore its path is deviated. Damage in the rock develops in the back of the crack tip, thereby enhancing the increase of permeability due to damage in the rock mass.

中文翻译：

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水力压裂的晶格建模：理论验证和与粘性节理的相互作用

摘要 提出了一种基于水力-机械耦合点阵的模型，用于模拟在含有粘性节理的多孔饱和岩石中由流体注入引起的裂纹扩展。岩石遵循拉伸断裂的各向同性损伤模型，而粘性节理遵循耦合的塑性-损伤模型。离散化使用双晶格方法：实体的 Delaunay 三角剖分和液压部件的关联 Voronoi 细分的边界。实现了用单一流体饱和的材料的经典多孔力学框架。首先，将裂纹扩展的预测与分析模型进行比较。然后，分析扩展裂纹和现有接头之间的相互作用。考虑了两种配置：与裂纹路径正交的接头的情况和相对于裂纹路径倾斜 45° 的接头的情况。对于竖向节理，由于粘性节理比岩体弱，裂缝首先被阻止。裂纹在两个裂纹尖端重新开始，随后在其中一个裂纹尖端扩展。对于倾斜接头，裂纹跟随接头，因此其路径偏离。岩体损伤在裂尖后部发展，从而促进岩体损伤引起的渗透率增加。裂纹跟随接头，因此其路径偏离。岩体损伤在裂尖后部发展，从而促进岩体损伤引起的渗透率增加。裂纹跟随接头，因此其路径偏离。岩体损伤在裂尖后部发展，从而促进岩体损伤引起的渗透率增加。