... Reservoir Characterization homogeneous rock brittle-ductile transition displacement rate fem dem code Upstream Oil & Gas axial stress confinement rock sample finite element fracture pattern transition specimen finite-discrete element method triaxial test structural geology...

... skeleton. Reservoir Characterization brittle-ductile transition cecconi evolution dilatancy constitutive equation plane viggiani internal variable stress ratio weak rock mechanical behaviour compression equation pyroclastic weak rock available experimental evidence grain size...