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为了研究地球介质中钻凿较深的斜井（这种井既受到内压又受到非静水应力场的作用），有必要发展一种分析表述方式·这种表述方式包括井孔周围应力的三维分析，并把它和井孔内压组合后，求出总应力分布的近似解·在实际现场条件下，井孔的取向、原地应力和岩层层面倾斜都可能是任意的·对井孔的拉伸破坏和剪切破坏都进行了研究·当井孔最小主应力超过拉伸强度时，出现拉伸破坏，这就是拉伸破坏准则·对剪切破坏而言，采用了各向异性材料的修正的Ｄｒｕｃｋｅｒ＿Ｐｒａｇｅｒ破坏准则·为了研究材料的各向异性、岩层面倾斜度和原地应力对井孔稳定的影响，进行了参量研究·参量研究结果表明，井孔稳定性明显地受到井孔高倾斜度、材料高度各向异性、原地应力条件和岩层面高倾斜度的影响·文中也研究了弹塑性介质中井孔的稳定性问题·为了弄清井孔周围塑性区范围的大小和塑性区内的材料各向异性性质，利用弹性理论和塑性理论给出了数学公式·同时还研究了竖直井孔在静水压力作用下，地球介质是横观各向同性时的钻井情况·为此，也对地球介质的塑性性能受材料各向异性的影响进行了参量研究·结果指出，井孔周围的应力分布、塑性区域的大小和破坏压力都深受材料各向异性程度和原地超负荷应力值的影响·我们观?
In order to study inclinations well deeper in the earth’s medium, which are subjected to both internal and non-hydrostatic stress fields, it is necessary to develop a way of analyzing and expressing them, including three-dimensional After combining it with the wellbore internal pressure, find an approximate solution to the total stress distribution. The hole orientation, in-situ stress and rock level tilt can be arbitrary under actual field conditions. Tensile failure and shear failure are studied. Tensile failure occurs when the minimum principal stress in the wellbore exceeds the tensile strength, which is the criterion for tensile failure. For shear failure, anisotropic materials Modified Drucker_Prager failure criterion • Parametric studies were conducted to investigate the effect of material anisotropy, rock facet inclination and in-situ stress on wellbore stability. • Parametric studies show that wellbore stability is significantly affected by wellbore pitching Degree, Material Anisotropy, In Situ Stress Conditions, and High Inclination in Rock Faces. The stability of boreholes in elasto-plastic media was also studied In order to clarify the size of the plastic zone surrounding the wellbore and the anisotropy of the material in the plastic zone, the mathematical formula is given using the theory of elasticity and plasticity. In addition, under the action of hydrostatic pressure, Earth’s medium is a case of transversely isotropic drilling. To this end, a parametric study of the plasticity of the Earth’s medium by the anisotropy of the material was also conducted. The results show that the stress distribution around the wellbore, the size of the plastic zone, and Destructive pressure is deeply affected by the degree of anisotropy of the material and the value of overburden stress in situ · What is our view?