Abstract
In this paper, the mechanical response of rock mass to high-pressure hydraulic injections applied during hot dry rock (HDR) stimulation is studied. The sliding of natural joints originated by the action of water pressure is assumed to be the governing mechanism of hydraulic fracturing. The constitutive relationship for the mechanical behavior of jointed rock mass under hydraulic fracturing is formulated by the extension of the MBC (micromechanics based continuum) model which is developed for mechanical behavior of jointed rock mass under excavation. Numerical simulation of hydaulic fracturing injection at Hijiori, Japan is conducted. The numerical results are in agreement with experimental data.
