准确测量和计算抗拉强度是进行煤岩物理力学性质研究以及开展煤层气井水力压裂设计的重要前提.首先开展了不同面割理倾角下的煤岩巴西劈裂试验,分析煤岩试样抗拉强度随面割理倾角的变化规律,推导了考虑不同面割理倾角和割理密度影响下的煤岩抗拉强度计算模型,并分析了煤岩层理对抗拉强度计算结果的影响.理论计算和试验结果对比分析表明,割理发育方向对抗拉强度有显著的影响,但层理对强度的影响并不显著.该研究对于进行煤层钻井井壁稳定性评价以及后续的压裂施工设计具有理论指导意义.%Accurate measurement and estimation of tensile strength is the important prerequisite in coal, rock physical and mechanical properties study and CBM well hydrofracturing design. Start with coal and rock Brazilian splitting tests under different face cleat dip an-gles, analyzed variation pattern of sample tensile strengths along with varying face cleat dip angles. Then deduced coal and rock tensile strength computation model considering impact from different face cleat dip angles and cleat densities;analyzed impact from coal and rock beddings on tensile strength computed results. The contrastive analysis of results from theoretical computation and sample test have shown that the cleat development direction can significantly impact tensile strength, but not large. The study has theoretical guid-ing significance in CBM well drilling wall stability assessment and subsequent hydrofracturing design.
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