Abstract During the process of reservoir stimulation, how to create more fractures has become a key issue for the tight sandstone reservoir development. From the experimental investigation and numerical simulation, the effect of pore pressure distribution on fracture propagation was analyzed. The experiment consisted of 300 × 300 × 600 mm3 sandstone specimens was divided into two laboratory tests to investigate the fracture propagation of simultaneous fracturing and sequence fracturing subjected to true tri-axial confinement stresses. The experimental results showed that the fracture distribution was asymmetric due to the influence of pore pressure and stress field. Meanwhile, the numerical simulation results discovered that the increase of pore pressure can not only cause the deflection of fracture, but also increase the breakdown pressure and extension pressure of rock. When the pore pressure increment was over 4 MPa, the fracture deflected obviously in the process of extension, and the breakdown pressure and extension pressure can increase by 22.8% and 23.05%.

中文翻译：

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孔隙压力分布对致密砂岩多裂缝扩展影响的实验与数值研究

摘要 在储层改造过程中，如何创造更多裂缝成为致密砂岩储层开发的关键问题。通过实验研究和数值模拟，分析了孔隙压力分布对裂缝扩展的影响。该实验由 300 × 300 × 600 mm3 砂岩试样组成，分为两个实验室试验，以研究在真实三轴约束应力下同时压裂和序列压裂的裂缝扩展。实验结果表明，受孔隙压力和应力场的影响，裂缝分布不对称。同时，数值模拟结果发现，孔隙压力的增加不仅会引起裂缝的偏转，同时也增加了岩石的破裂压力和伸展压力。当孔隙压力增量超过4 MPa时，裂缝在伸展过程中发生明显偏转，破裂压力和伸展压力分别增加22.8%和23.05%。