Basic Principles of Thin-Walled Open Bars Taking into Account Where Influence Shifts of Cross Sections are Concerned

[摘要] The finite element method is considered to be the most effective in relation to the calculation of strength and stability of buildings and engineering constructions. As a rule, for the modelling of supporting 3-D frameworks, finite elements with six degrees of freedom are used in each of the nodes. In practice, such supporting frameworks represent the thin-walled welded bars and hot-rolled bars of open and closed profiles in which cross-sectional deplanation must be taken into account. This idea was first introduced by L N Vorobjev and brought to one of the easiest variants of the thin-walled bar theory. The development of this approach is based on taking into account the middle surface shear deformation and adding the deformations of a thin-walled open bar to the formulas for potential and kinetic energy; these deformations depend on shearing stress and result in decreasing the frequency of the first tone of fluctuations to 13%. The authors of the article recommend taking into account this fact when calculating fail-proof dynamic systems.

[发布机构] Engineering and Technology of Land Transport, Astrakhan State Technical University, Tatischeva St., 16, Astrakhan; 414056, Russia^1;Industrial and Civil Construction, Astrakhan State University of Civil Engineering, Tatischeva St., 18, Astrakhan; 414056, Russia^2

[学科分类] 土木及结构工程学

[关键词] Basic principles;Deplanation;Engineering constructions;Hot rolled bars;Shearing stress;Six degrees of freedom;Thin-walled