FRACTURE BEHAVIOUR OF CONCRETE AND ROCK UNDER MODE II AND MODE III SHEAR LOADING. FRACTURE OF CONCRETE AND ROCK: RECENT DEVELOPMENTS. PAPERS PRESENTED AT THE INTERNATIONAL CONFERENCE, UNIVERSITY OF WALES, COLLEGE OF CARDIFF, SCHOOL OF ENGINEERING, SEPTEMBER 20-22, 1989

Failure of geomaterials such as concrete and rock, in the form of cracks, involves not only mode I in tension but also mode II and mode III shear fracture. This paper proposes an experimental analysis of the fracture behaviour of concrete and rock under mode II and mode III shear loading in order to evaluate the influence of dilatancy phenomenon on the fracture mechanism of these materials under the combined action of normal and shearing stresses. The compressive stress normal to the failure surface is respectively imposed or monitored with a given stiffness in order to obtain Mohr's limiting stress curve and the dilatancy effect occurring at failure.(A) For the covering abstract of the conference see IRRD 829348.