Gong Xun, Jin Zhijun, Ma Xinhua, Liu Yuyang, Li Guanfang, Guo Yanjun
Institute of Energy, Peking University, Beijing, 100871, China.
School of Earth and Space Sciences, Peking University, Beijing, 100871, China.
Sci Rep. 2025 Jul 1;15(1):20716. doi: 10.1038/s41598-025-07039-w.
The interaction mechanism between hydraulic fractures (HF) and natural fractures (NF) constitutes a critical research focus in hydraulic fracturing optimization. This study systematically investigates the influence of NF curvature on HF propagation behavior through large-scale true triaxial hydraulic fracturing physical simulations. The experiments were conducted on artificial rock specimens containing prefabricated fractures with varying curvature parameters. Results show that the curvature of natural fractures have important effects on the interaction between hydraulic fractures and natural fractures. When the injection rate is constant and the approximation angle is 90°, with the curvature of the natural crack gradually increasing (increasing curvature), the interaction between the hydraulic fracture and the natural fracture shows that the hydraulic fracture passes through the natural fracture and also partially extends along the natural fracture, and gradually changes to the hydraulic fracture extending only along the natural fracture, and then finally exists the natural fracture and extends along the direction of the maximum horizontal principal stress. In addition, the increase in curvature of the natural fractures leads to a decrease in fluid pressure as the hydraulic fractures interact with the natural fractures. The experimental methodology and results contribute to fundamental understanding of fracture propagation mechanics in heterogeneous media, with direct applications to stimulation design in naturally fractured reservoirs.
水力裂缝（HF）与天然裂缝（NF）之间的相互作用机制是水力压裂优化中的一个关键研究重点。本研究通过大规模真三轴水力压裂物理模拟系统地研究了天然裂缝曲率对水力裂缝扩展行为的影响。实验在含有不同曲率参数预制裂缝的人造岩石试件上进行。结果表明，天然裂缝的曲率对水力裂缝与天然裂缝之间的相互作用有重要影响。当注入速率恒定且近似角度为90°时，随着天然裂缝曲率逐渐增大（曲率增加），水力裂缝与天然裂缝之间的相互作用表现为水力裂缝穿过天然裂缝并部分沿天然裂缝延伸，然后逐渐变为水力裂缝仅沿天然裂缝延伸，最后天然裂缝存在并沿最大水平主应力方向延伸。此外，随着水力裂缝与天然裂缝相互作用，天然裂缝曲率的增加导致流体压力降低。该实验方法和结果有助于从根本上理解非均质介质中的裂缝扩展力学，直接应用于天然裂缝性油藏的增产设计。
