为了分析页岩的层理和水化损伤对钻井过程中井壁稳定性的影响，开展室内岩石三轴力学试验测试页岩原始状态和钻井液作用不同时间的力学特性；然后基于孔隙弹性理论和岩石弱面强度理论，综合考虑层理产状和水化损伤对页岩强度的影响，建立页岩地层井壁稳定性分析模型。结果表明：层理产状和水化损伤对井壁稳定性有显著的影响，都会导致坍塌压力升高，加剧井壁的不稳定性。综合考虑页岩的层理和水化损伤两个因素分析地层井壁稳定性，对优化不同时段钻井液性能，调整钻井液密度，保证钻井安全有重要意义。%In order to analyze the influence of bedding and hydration damage of shale on wellbore stability in drilling process, the laboratory triaxial mechanics tests of rock were conducted to test the initial conditions of shale and its mechanics charac-teristics under different action time of drilling fluid. Based on the poroelastic theory and the rock weak plane strength theory, an analysis model on wellbore stability in shale formation was established with comprehensively considering the influence of bedding attitude and hydration damage on shale strength. The calculation results showed that the bedding attitude and hydra-tion damage have significant effects on wellbore stability, and both of them will cause the increase of collapse pressure and exacerbate the wellbore instability. The analysis on formation wellbore stability with comprehensively considering both the factors of bedding attitude and hydration damage has great significance for optimizing the performance of drilling fluid in dif-ferent time period, adjusting the density of drilling fluid and ensuring the drilling safety.
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