裂隙岩体断裂破坏扩展数值模拟研究

为进一步了解复杂裂隙断裂破坏过程，基于断裂力学理论，采用PFC2D软件对不同裂隙数量岩体进行数值试验，分析裂隙倾角、围压等因素对岩体强度及裂纹扩展的影响规律。研究表明：随着裂隙倾角增大，单裂隙峰值应力和起裂应力先减小后增大，当围压由2 MPa增加到8 MPa时，峰值应力约从120 MPa增大到160 MPa,且起裂应力随着围压增大而增大，与理论分析结果一致；双裂隙倾角为30°和45°裂隙扩展以翼型裂纹和次生斜裂纹为主，裂隙倾角为60°和90°时主要为共面次生裂纹；不同围压下，随着预制裂隙数量增多，裂隙岩体试样峰值应力逐渐减小。研究成果为进一步探索裂隙岩体失稳破坏规律提供参考。

Study on Fracture Failure Propagation of Fractured Rock Mass Based on Numerical Simulation

To further understand the fracture damage process of complex fractures, this paper uses PFC2D software to conduct numerical tests on rock masses with different number of fractures based on the fracture mechanics theory, and analyses the influence of fracture dip angle, surrounding pressure and other factors on the strength and fracture expansion of rock masses. The study shows that the peak stress and initiation stress of single fracture decrease and then increase as the fracture inclination angle increases, and the peak stress increases from 120 MPa to 160 MPa when the surrounding pressure increases from 2 MPa to 8 MPa. In cases of 60° and 90°, the fracture inclination is mainly coplanar secondary fractures, and the peak stress of multiple fractures decreases significantly with the increase of the number of prefabricated fractures at different surrounding pressures. The research results can provide reference for further exploration of the destabilization damage law of fractured rock masses.