Cracking mechanism of shale cracks during fracturing

2018 International Conference on Material Strength and Applied Mechanics

材料科学;力学

Zhao, X.J.^1,2 ; Zhan, Q.^1,2 ; Fan, H.^2 ; Zhao, H.B.^3 ; An, F.J.^4

School of Aeronautics, Northwestern Polytechnical University, Xi'an, Shanxi

710072, China^1

School of Electronic Engineering, Xi'An Shiyou University, Xi'an, Shanxi

710065, China^2

Xi'An Center of Geological Survey, Shanxi, Xi'an

710054, China^3

Dongying Shengfeng Safety Service Corporation, Shandong, Dongying

257000, China^4

关键词: Cracking mechanisms;    Different water contents;    Drilling engineering;    Elastic-Plastic;    Fracture pressures;    Stress criterion;    Technical support;    Tectonic stress fields;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/372/1/012046/pdf
DOI  :  10.1088/1757-899X/372/1/012046

来源: IOP

【 摘 要 】

In this paper, we set up a model for calculating the shale fracture pressure on the basis of Huang's model by the theory of elastic-plastic mechanics, rock mechanics and the application of the maximum tensile stress criterion, which takes into account such factors as the crustal stress field, chemical field, temperature field, tectonic stress field, the porosity of shale and seepage of drilling fluid and so on. Combined with the experimental data of field fracturing and the experimental results of three axis compression of shale core with different water contents, the results show that the error between the present study and the measured value is 3.85%, so the present study can provide technical support for drilling engineering.