The stress-plastic dilatancy relationship was investigated for crushed concrete during drained and undrained triaxial compression tests in the light of the frictional state concept. The slope of the dilatant failure state line is greater than that of quartz sand for drained triaxial compression due to the crushing effect. The crushing effect parameters for drained and undrained conditions are very similar. Due to the very angular shape of crushed concrete grains, the crushing effect is observed at low stress levels. Some characteristic behaviors of geomaterials during shear are visible only in the stress ratio-plastic dilatancy plane and are very rarely presented in the literature. The stress ratio-plastic dilatancy relationship, which is basic in elastic-plastic modeling of geomaterials, can be described using the frictional state concept.
Keywords: crushed concrete; frictional state concept; stress–dilatancy; triaxial compression tests.