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

Table 4

Numerical simulation scheme.

No.	Principal stress (MPa)	Borehole spacing D (mm)	Angle θ between borehole direction and σ1. (°)
A1	σ1 = 11, σ3 = 9	225	15°
A2	σ1 = 11, σ3 = 9	225	30°
A3	σ1 = 11, σ3 = 9	225	45°
A4	σ1 = 11, σ3 = 9	225	60°
A5	σ1 = 11, σ3 = 9	225	75°
B1	σ1 = 11, σ3 = 9	200 (5d)	40°
B2	σ1 = 11, σ3 = 9	240 (6d)	40°
B3	σ1 = 11, σ3 = 9	280 (7d)	40°
B4	σ1 = 11, σ3 = 9	320 (8d)	40°
B5	σ1 = 11, σ3 = 9	360 (9d)	40°
C1	σ1 = 11, σ3 = 10	225	40°
C2	σ1 = 11, σ3 = 8	225	40°
C3	σ1 = 11, σ3 = 6	225	40°
C4	σ1 = 11, σ3 = 4	225	40°
C5	σ1 = 11, σ3 = 2	225	40°