The article describes the results of laboratory experiments conducted on a unique setup, which allows to model not only the process of hydraulic fracturing, but also to vary the external conditions. The advantages of the setup include the ability to model such tasks: reorientation of a hydraulic fracture due to the stress state changes caused by the development of the field; the formation of unstable fractures in the injection wells; verification of hydraulic fracturing simulators used in oil producing companies. The setup allows to study large samples (0.43 m in diameter, 0.07 m in height). It is possible to place in the sample not only a model well with fracturing, but also adjacent wells. Thus, we can model part of the development system and its effect on hydraulic fracture propagation. Also, a non-uniform three-dimensional stress-strain state which largely determines the geometry of the fracture can be created with the setup. The experiments were aimed at the study of the problems described above. It was found that the pore pressure distribution created by the development of neighboring wells can actually influence the fracture trajectory. Also, the influence of existing fractures on the propagation of a new fracture was established. In addition, in the experiment it was possible to obtain a refracture. The presented experimental results allow a better understanding of the formation of real hydraulic fracturing, which should be taken into account in the numerical simulation.
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