Abstract To quantitatively evaluate the influence of high true three-dimensional stresses on ductile–brittle behaviours rock in deep underground engineering, a series triaxial compression tests with different stress levels were carried out marble and four kinds granite. The influences states ( σ 2 , 3 ) post-peak characteristics analysed, new normalized evaluation index was proposed based energ...

Evolutionary and cognitive examples are used to motivate an approach to the brittleness problem and automated flexible cognition, centering on the notion of an anomaly as the key focus of processing.