Brittleness Evaluation of Saturated Coal Based on Energy Method from Stress–Strain Curves of Uniaxial Compression

Rock brittleness is an important index evaluating geotechnical stability and failure mode, and it is also influenced by pore fluid pressure, especially in deep underground mining. To evaluate the brittleness from stress–strain curves of uniaxial compression, uniaxial compressive tests were carried out on water-pressurized coal samples, and a new energetic brittleness index was proposed. The saturated coal samples were classified into brittle,...