Investigation of nonlinear oscillations of high rise flue gas stacks under various kinematic effects

Abstract

A detailed analysis of the current state of the problem is presented in the article. A mathematical model is given to assess the dynamic behavior of high-rise structures, considering geometric nonlinearity (nonlinear dependence of strains on displacements) under periodic kinematic effects and the own weight of the structure. The unsteady forced oscillations of the high-rise flue gas stack of the Novo-Angrenskaya HPP were studied considering the geometric dimensions of the stack and the physical and mechanical characteristics of the material of the structure. The influence of dissipation in the material, leading to rapid or gradual damping of vibrations depending on the frequency spectrum of natural vibrations in one direction or another, as well as geometric nonlinearity, leading to an increase in the amplitude of vibrations at a low energy dissipation in the structure, and resonant impact, causing significant displacements of the structure. The predominant effect of energy dissipation in the material on the pattern of the dynamic behavior of a high-rise structure is observed compared to geometric nonlinearity.