Stress Determination in Rock Mass by Fracture Propagation Pressure Nearby Cylindrical Opening
A. V. Azarov, S. V. Serdyukov
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Rock mass, mine opening, stress state, hydraulic fracturing, fracture propagation pressure, fracture trajectory, numerical modeling, extended finite element method, stress determination
Abstract
The article describes numerical investigation of usability of fracture propagation pressure in stress assessment of rock masses. Development and testing of the proposed approach involved 3D numerical experimental modeling of hydraulic fracturing nearby a cylindrical cavity. The main equations in the model were solved using the extended finite element method. The patterns of variation in the fracture propagation pressure nearby the cylindrical cavity are obtained. The relations are presented to find stresses in uniform compression and in a nonuniform field when the minimal stress acts in perpendicular to the axis of the cavity. It is studied how the error of the method changes depending on the ratios of the model parameters. It is shown that in some cases, it is possible to assess direction of the minimal stress by the hydraulic fracture trajectory, its exposure and propagation pressure.
|
