The Impact of Lateral Restraint on Structural Stability of Thin-Walled C-Cross Section Column Subjected to Axial Force

Abstract

SummaryThe paper analyses the impact of lateral restraining by trapezoidal steel sheeting on the structural stability of thin-walled C-cross section columns subjected to axial forces. Firstly, mechanical properties of the column material (steel) and lateral stiffness of the rotational restraint are determined by testing standard specimens in a laboratory. Based on the obtained data, a stability analysis of unrestrained columns and of columns laterally restrained by trapezoidal steel sheeting has been carried out and critical forces have been determined analytically by using the theory of thin-walled beams, numerically by using the finite element method (FEM), and experimentally by testing the C-cross section columns in a laboratory. The analysis of critical forces and stability shows that the calculation according to the theory of thin-walled beams and the FEM calculation gives results similar to the results of the experimental tests. By comparing the results of the investigation into thin-walled C-cross section columns with and without lateral restraints a significant influence of lateral restraints on the stability of thin-walled C-cross sections subjected to axial forces has been proven: lateral restraint significantly affects final results of the level of the critical force, raising the possibility of optimizing the use of such structures in practice.

Effect of Lateral Restraint on Buckling Behaviour of a Thin-Walled Z-Section Column

“…It is higher than for the design values according to EC3 (100%). If we compare results with the buckling of the C-cross section models, the influence of lateral restraining on the Z-cross section columns is greater [8]. Relative increase of critical forces for the C-cross section is about 57% [8], while for the Z-cross section it is 150%.…”

“…2). Such models are specifically selected to expand previous research on the C-cross-section models [8].…”

“…Torsional stiffness, realised by adequately fastened sheeting, with ribs perpendicular to the column, is determined according to Eurocode 3 (EC3) [11]. Laboratory tests and the analytical solution are combined and the rotational stiffness = 0.9 kNm/m/rad is determined [8].…”

“…Existing researches mainly apply to the stability of thin-walled open cross section beams, where analyses are limited to beams subjected to gravity or lifting load defined by various standards [5][6][7]. On the contrary, behaviour of laterally restrained axially loaded column has not been the subject of systematic research, and satisfactory treatment by modern standards is missing [3,8].…”