Modelling damage mechanisms of concrete under high confinement pressure

•Three damage mechanisms of concrete subjected to intensively dynamic loadings are identified and physically modelled.•The hydrostatic damage and shear damage models can well reproduce the test data demonstrated by numerical single element tests.•The competition mechanism of hydrostatic damage and shear damage during a triaxial compression test is well captured.•Physical mechanisms of experimentally observed crater, crack, tunnel and spall failures in concrete structures are revealed.