Abstract:In order to study the laws of fracture propagation meeting skew bedding. The concentration stress solutions of arbitrary crack tip were obtained by complex functions,conformal transformation and coordinates transformation. Compared the stress state and strength at original fracturing direction with bedding,the hydraulic fracture propagation when fracture vertical minimum in-situ stress meet skew bedding were obtained based on the maximum tensile stress criterion.The indexes,namely the critical intensity ratio,show the difficulty of fracture turning to bedding,which decreases indicate that fracturing turned to bedding demanding the ratio of bedding and rock matrix strength have to be smaller. The critical intensity ratio was influenced by in-situ stress state,strength of the rock matrix and bedding and bedding orientation. It heightens when the difference of maximum or middle principal stress with minimum principal stress reduced and when the angle between bedding with fracture surface decreased. It lessens when rock matrix tensile strength and the angle between intersecting line of bedding and fracture surface with middle principle stress declined. The rules of analytical solution and experimental results compared have no difference.
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