Collapse behaviour of triangular cross-section girders subject to pure bending

Abstract Plastic mechanisms of failure of triangular cross-section girders subjected to pure bending are considered in this paper. Theoretical models of four basic plastic mechanisms observed during preliminary experimental model investigation are described. Theoretical analysis is carried out using basic assumptions of the general rigid plastic theory and particular assumptions concerning thin-walled structures. The total energy of plastic deformation as well as the bending moment of the global plastic hinge are formulated. Example of numerical results relating to one of considered plastic mechanisms is presented.