Refinement of the accounting methodology of bi-moments transfer at the junctions of the I-section bars

21st International Scientific Conference on Advanced in Civil Engineering "Construction - The Formation of Living Environment"

土木建筑工程

Serpik, Igor^1 ; Shkolyarenko, Roman^1

Bryansk State Engineering and Technology University, Stanke Dimitrov av. 3, Bryansk

241037, Russia^1

关键词: Calculation algorithms;    Calculation models;    Construction standards;    High degree of accuracy;    Plate finite elements;    Relative positions;    Restrained torsion;    Thin-walled construction;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/365/4/042011/pdf
DOI  :  10.1088/1757-899X/365/4/042011

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

Modern construction standards require an accounting of bi-moments when determining normal stresses in the cross-sections of the bars. This factor may first be essential to provide the required safety and reliability of thin-walled bars of an open profile. The bars restrained torsion theory was sufficiently considered in literature, however, in recent years the classic concepts about interaction of such bars in frame systems have been challenged by some authors. Within the framework of the finite element method such problem may be solved on the basis of a combined approach, when the bar finite elements are imposed out of the area of joined nodes and strains at the joints are described with the help of plate finite elements. At the same time, calculation models become more complicated in comparison to using only the bar finite elements. In this paper the detailed studies of interaction of the bars with I-sections are performed on the basis of mathematical modeling of their strains with the help of plate finite elements. The methodology of these studies contains definition of bi-moments in several bars cross-sections, including the sections adjacent to the joints. Different variants of relative positions of the bars are considered. It has been determined that in some instances the condition of bi-moments balance is provided in assembly joints with a high degree of accuracy. At the same time, in some schemes of the bars connection such a balance is being largely damaged. The paper gives the explanation for the phenomenon based on the features of the transfer of the internal forces factors in the connection joints of the bars. It also represents a way of obtaining imbalance on bi-moments in accordance with the real work condition of these thin-walled constructions. The obtained results will make it possible to increase the accuracy of calculations of the thin-walled constructions formed by the bars with I-sections within the bars calculation models. The considered approach to the analysis of the interaction of the thin-walled bars may be the basis for development of the calculation algorithms of thin-walled bar systems with other forms of cross-sections.