Research of changes in the parameters that affect the rigidness of the column-foundation joints

Abstract

Introduction. The existing types of connection assignment in the design scheme — hinged and absolutely rigid joints — do not reflect the actual operation of the connection. The lack of calculation of the actual rigidness of joint and its failure to take into account in the design of the frame can lead to a different distribution of efforts from the calculated one and an increase in the movement of the frame elements. The purpose of this work is to researching the influence of the change size of the elements forming the column base on its rotational rigidity. Materials and methods. The calculation of the transverse frame was performed in the Dlubal RFEM software package. The calculated efforts acting in the lower section of the column were transferred to the calculated models of the column base, made in the IDEA StatiCa software package, in which the further calculation of the joint rigidness was performed. Results. The rotational rigidness of the joints with different structural solutions of the column base is determined. The change in the rigidness of the connection between the column and the foundation with an increase in the thickness and height of the support ribs is analyzed. Based on the calculations, graphs of the identified dependencies are constructed. As an example of strengthening the base of the column, the introduction of a traverse was proposed. The article considers six variants of the traverse device, and variants with three support ribs and with traverses, but without support ribs. The calculated rigidness of the column bases is summarized in graphs, where it can be seen that the metal adding is effective only up to a certain point. Variants of the arrangement of column bases with additional transverse ribs are considered. Conclusions. The greatest contribution to the increase in the rotational rigidness of the joint is made by the addition of a traverse. By increasing the thickness or height of the introduced traverse, it is impossible to achieve absolutely rigid fixing, it is necessary to change several parameters in a complex way. The introduction of additional ribs located outside the plane of action of the moment practically does not affect the rigidity of the joint.