Research Article

Mechanisms of Crack Initiation and Propagation in Dense Linear Multihole Directional Hydraulic Fracturing

Figure 5

Crack propagation of directional hydraulic fracturing controlled by dense linear multihole drilling. (a) Crack along ligature of holes (specimen A). (b) Hydraulic cracks along ligature of holes and σ1 (specimen B). (c) Hydraulic cracks totally along σ1 (specimen C).
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(b)
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