composite hybrid rods, metal-plastic, concrete-plastic, wood-plastic, metal-ceramic structures, criteria for ultimate deformations, ultimate loads.

For composite rods with arbitrary constant cross sections and piecewise constant along the axis of the reinforcing structures various phase nature loaded with axial loads, the general dependencies between the parameters of geometric structures, physico-mechanical characteristics of materials and coordinates of application of axial loads, ensuring a rational cross-section deformation field. Based on the concept of the weakest link, the criteria for determining the first (ultimate elastic) and the second ultimate load (pre-fracture load).

Nemirovskii Yuri Vladimirovich,

Dr. Sci. Phys. & Math., Professor, Leading Research Worker, S. Khristianovich Institute of Theoretical and Applied Mechanics of the Siberian Branch of the RAS, Novosibirsk, Russia.