The study presents theory of layered axially compressed cylindrical rods (shells with a core). The author analysed problems of critical loads in elasto-plastic states. The plasticity ratio of a critical transverse section was defined by the angleα , and was related to the slenderness ratio of rods. The obtained theoretical results were compared with the experimental results of rods made of R35 steel (Standard PN-73/H-74240).
A description of the folding phenomenon of thin-walled cylindrical axially compressed rods during loss of stability in plastic states is presented in the paper. The course of quasi-static load and rod deformation thanks to simultaneous camera filming with the divided screen method is analysed. Changes of crystal grains in a polished cross-section before and after the experiment made on a R35 steel rod (PN-73/H-72240) are presented.
W pracy poddano ocenie siłę krytyczną w pręcie wspornikowym poddanym działaniu niekonserwatywnej siły osiowej. Zastosowano statyczne i dynamiczne kryterium utraty stateczności przez bifurkację i flater. Wpływ parametru,α charakteryzującego obciążenie niekonserwatywne, przeanalizowano z punktu widzenia analizy wrażliwości.