Brittle-Ductile Transition and Hoek–Brown mi Constant of Low-Porosity Carbonate Rocks

The mechanical behavior of low porosity carbonate rocks is investigated by a series of conventional triaxial compression tests performed at room temperature, at various confining pressures up to 70 MPa and at a constant strain rate of 5 × 10 −5 s−1. Aiming at an improvement of the accuracy and quality of the constant mi of the non-linear Hoek–Brown criterion for jointed rock, four dense, high strength and low-porosity carbonate rocks were tested...