Shapes of Hydraulic Fractures in the Vicinity of Borehole-and-Branch Hole Junction

• Published in: Journal of mining science Vol. 58; no. 5; pp. 741 - 753
• Main Authors: Azarov, A. V., Patutin, A. V., Serdyukov, S. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-10-2022; Springer; Springer Nature B.V
• Subjects: Boreholes; Compression; Crack propagation; Earth and Environmental Science; Earth Sciences; Failure modes; Finite element method; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Hydraulic fracturing; Mineral Resources; Nonuniformity; Rock Failure; Three dimensional analysis; numerical investigations; intersecting boreholes; fracture trajectory and shape; mathematical modeling; stress state; borehole with branch hole; directional hydraulic fracturing; rock mass; fracture
• ISSN: 1062-7391; 1573-8736
• DOI: 10.1134/S1062739122050052

The authors describe numerical investigations of hydraulic fractures in boreholes with branches (intersecting boreholes). The directions of growing fractures were determined in the static problem solution by the criterion of maximum tangential stresses and in the quasi-static three-dimensional formulation with the analysis of fracture of an elastic uniform medium using the cohesive failure mode and the extended finite element method. It is found that some geometrical parameters of the starter fracture and the stress state nonuniformity have influence on the growth direction and shape of the created fractures. The X-shaped starter fracture, which simulates branching and intersections of boreholes, is preferable over the disc-shaped starter fracture in local control of hydraulic fracture orientation in rock mass under nonuniform compression.