Network fracturing technology of hydraulic fracturing in coalbed methane reservoir based on induced stress

The stimulated reservoir volume (SRV) fracturing is used to consider the effects of natural fractures in the fracture network formation. Meanwhile, the importance of the operation itself is often disregarded. To improve the oil and gas recovery factor, a reservoir reconstruction technique based on induced stress is examined. In this paper, we applied the theory of elastic–plastic mechanics to evaluate the induced stress of net pressure on the fracture plane during the fracturing process. A mathematical model of a fracture-induced stress field was established and combined with the distribution of the in situ stress field. The stress field around the fracture during fracturing is thereby elucidated. Based on this research, it is evident that fracture-induced stress has disparate variation regularity in different directions. Overall, the induced stress is the largest in the direction perpendicular to the fracture plane. It gradually decreases along the farther distance from the fracture plane until it disappears. This induced stress can change the stress field distribution around the fracture by enhancing the net pressure on the fracture plane. A method applied in stages to change the treatment pressure fully leverages the characteristics of induced stress, thereby causing the stress relations to change around the fracture plane. This provides good conditions for a new crack formation and a wider range of fracture network transformations.