Longitudinal stability of the rod using an actual diagram of steel.

The article considers the calculation of the stability of the rod, taking into account the actual work of the steel. Based on experimental data on the stretching of steel samples, an array was formed that was used to construct a piecewise linear diagram of the material. This diagram was used in numerical modeling of a rod with finite stiffness in an ANSYS Mechanical PC. Calculations of the stability of the rod have been performed taking into account the actual work of steel (piecewise linear diagram) and using a Prandtl bilinear diagram according to SP16.13330 (hereinafter SP16) for rods with conditional flexibility from 1 to 7. For comparison, the maximum critical load of the rod was also calculated using the analytical formulas SP16 for both the central and off-center compressed rod. The results showed that taking into account the actual work of steel significantly affects the accuracy of the calculation. In addition, it was noted that the calculations for SP16 lead to an overestimation of the critical load for a centrally compressed rod, which requires a revision of the current version for a more accurate assessment of overall stability. The possibility of approximating the area of elastic plastic work of steel by a piecewise linear diagram is shown.