This work designs an experimental model of tight sandstone with a closed cemented pre-existing fracture network (CCPF) to explore the influence of closed cemented natural fractures on the propagation behavior of hydraulic fracture (HF) in tight sandstone formations. The influence of CCPFs with different directions on the initiation, deflection, and propagation of HF is studied based on tri-axial hydraulic fracturing experiments with acoustic emission (AE) monitoring technology. The experimental results show four types of interaction behavior between HFs and CCPFs: deflection I; deflection II; penetration; and composite pattern. When the angle (α) between the HFs and CCPF is 0° ± 15°, their interaction is deflection I. During the process of hydraulic fracturing, the CCPF open with few AE events. When α = 90° ± 15°, the interaction between the HF and CCPFs includes deflection II and penetration patterns. The HF mainly extends in the rock matrix and is accompanied by significant AE events. When α = 45° ± 15°, the interaction is complicated and includes composite and deflection I patterns. The accumulated AE energy of composite interaction pattern shows a ladder-type increase. Under the same in-situ stress conditions, the HF geometry is the most complicated with the largest number of communicated natural fractures when the angle between the maximum principal horizontal stress direction and CCPF is 30°–60°. The experimental model designed in this paper can reproduce the complex propagation patterns of HFs in fractured tight sandstone formations, and the results provide a reliable basis for follow-up theoretical studies and engineering applications.

这项工作设计了一个封闭的胶结现有裂隙网络（CCPF）的致密砂岩实验模型，以探索封闭的胶合天然裂缝对致密砂岩地层中水力压裂（HF）传播行为的影响。基于声发射监测技术的三轴水力压裂实验，研究了不同方向的CCPF对HF的发生，偏转和传播的影响。实验结果表明，HF和CCPF之间有四种相互作用行为：挠度I；挠度I；挠度I；挠度I。挠度II; 渗透; 和复合模式。当HF与CCPF之间的夹角（α）为0°±15°时，它们的相互作用为挠度I。在水力压裂过程中，CCPF很少发生AE事件。什么时候α  = 90°±15°，HF和CCPF之间的相互作用包括挠度II和穿透模式。HF主要在岩石基质中延伸，并伴有大量的AE事件。当α = 45°±15°，相互作用很复杂，包括合成和偏转I型图。复合相互作用模式的累积AE能量呈梯形增加。在相同的原地应力条件下，当最大主水平应力方向与CCPF之间的夹角为30°–60°时，HF的几何形状最复杂，连通的自然裂缝数量最多。本文设计的实验模型可以再现裂隙致密砂岩地层中HFs的复杂传播规律，为后续的理论研究和工程应用提供可靠的依据。