hybrid, layered, polygonal plates, right angle, articulation, pinching contour, the concept of the weakest link, the first and second limit loads, subclasses of rational and not quite rational hybrid structures.

For a class of hybrid polygonal plates with contours having a right angle under various loading and securing conditions, an engineering method has been developed for determining the first (extremely elastic) and second (pre-fracture) ultimate loads. The criteria for their achievement were determined, the necessary systems of resolving equations were obtained, and the method for solving them was described.

Yuri Vladimirovich Nemirovsky, Dr. Sci. Phys. & Math., Chief Researcher, Institute of Theoretical and Applied Mechanics S. A. Khristianovich SB RAS, Novosibirsk; Professor, Novosibirsk state technical University, Novosibirsk, Russia.