Различные аспекты учета давления жидкости и газа в задачах статики гибких стержней

Abstract

In some practical applications, bars are loaded with the pressure of liquids and gases. Although the work of such objects is well studied and described in a large number of papers, some of the latter have wrongful provisions. For example, the equilibrium equations of a pipeline often include axial force instead of equivalent force, which reduces the accuracy of estimating the bending shape and acting stresses. The problem of accounting for pressure is due to the objectively more complex type of this loading in comparison with the forces of weight and insufficient distribution of the known provisions in engineering. This review and methodological paper focuses on a set of issues related to the loading of a bar by pressure. In the research, first, we obtained vector and linearized equations of equilibrium of the bar taking into account the load from the surface pressure. Then, we substantiated the equivalence of loading the bar with pressure and weight load determined by Archimedes’ law. Finally, we gave provisions for taking into account the pressure in the study of the equilibrium, stability, deformation, and strength of the bar. As an example, the effect of pressure in the problems of laying a pipeline on the seabed and evaluating the longitudinal stability of the bar is shown.