Prediction of the Orientations of Main Cracks caused by Hydrofracturing in Strained Rock Samples

摘要

We discuss experimental results dealing with crack propagation caused by hydrofracturing in strained rock samples and specify a coupled Boundary Element - Displacement Discontinuity (BE-DD) Method that is used to analyse fracture propagation in laboratory and field experiments. We find that the direction of the main crack propagation in the laboratory experiments may depend on stress concentrations close to edges of initial microcracks. Higherorder coupled BE-DD Method is used to solve two-dimensional problems. A new semi-analytical method to construct three-dimensional edge boundary elements is described.