TORSION IN THE ELEMENTS OF THE METAL DOME FRAME, SUPPORTED BY SPARSELY INSTALLED COLUMNS

Abstract

The effect of torsion on the stress state of the main elements of a metal ribbed-annular dome was investigated. The dependence of the torsion effect on the increase in the distance between the columns supporting the dome was revealed. At the same time, the dependence of torsion on the type of nodal junctions of the frame elements among themselves was determined. The object of the study was a ribbed-ring dome, all elements of which are made of steel pipes. The dome had different support schemes on columns of steel pipes, installed not under each rib, but cyclically symmetrical along the contour. There were four such schemes. In addition, the type of nodal connections of the frame elements to each other has been changed for each scheme. There were five different types of conjugations. The research was carried out through calculations of various models. There were twenty models in total. During the calculations, the stresses in the main elements of the dome models were determined, which were compared with each other. In this case, comparative diagrams of the stress state dependences of the elements of the ribbed-ring dome are obtained. The effect of torsion on the stress state of the elements of the ribbed-ring dome of the considered models is estimated. The degree of change in the stress state of individual frame elements due to torsion has been established. According to the results of the study, significant stress changes due to torsion in the upper ring and noticeable in the meridional ribs were noted. The dependence of the nature of their changes on the type of nodal connections has been established. It is recommended to take into account the torsion effect when designing metal rib-ring domes.