Lab-scale simulation of hydraulic fracturing: some outcomes

Abstract

The paper describes the lab-scale physical simulation of hydraulic fracturing in measurement holes. The tests were carried out using cubical polymethyl methacrylate specimens with faces of 200 mm. The open-end or dead-end holes with diameter of 12 mm were made in the test specimens. In the preset intervals in the holes, the longitudinal or latitudinal (ring-wise) slots with depths up to 3 mm were precut to initiate and orient created fractures. Hydrofracturing was carried out using prototype tools for sealing a test interval in a hole (packer-to-packer spacing) and to feed it with power fluid under pressure. The model specimens were tested under different triaxial loading conditions on a special testing machine. The representative cases of the created fracture growth in the model specimens were analyzed. The physical simulation outcomes can be used in formulation and solution of analytical problems on HF stress measurement, as well as to improve procedures and equipment involved in this method of stress control in underground mines.