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含节理裂隙的硬脆性泥页岩井壁坍塌是钻井工程中的难题。本文应用损伤力学理论，从岩体的变形能出发，建立了节理裂隙岩体的弹性损伤——断裂力学模型。由裂纹变形能推导出含节理裂隙的硬脆性泥页岩等效弹性损伤柔度张量，并推导出含节理裂隙岩体的真实应力求法。此力学模型将节理面几何特性与宏观力学特性联系起来。在预测此类岩石保持井壁稳定的泥浆密度时，只需知道损伤参数和完整岩石的强度参数，即可求出防止井壁坍塌的泥浆密度。
The hard and brittle shale with fractured joints is prone to collapse in wellbore engineering. Based on the theory of damage mechanics, from the deformation energy of rock mass, the elastic damage-fracture mechanics model of jointed rock mass is established. From the crack deformation, the equivalent elastic damage compliance tensor of hard and brittle shale with joint fractures can be deduced and the true stress method of the fractured rock mass containing the jointed fractures can be deduced. This mechanical model links the geometry of the joint surface with the macroscopic mechanical properties. In predicting the mud density of such rock to maintain a stable borehole wall, the density of the mud that prevents collapse of the borehole wall can be found by knowing the damage parameters and the strength parameters of the intact rock.