Influence of Warping on Modal Parameters of Thin-walled Channel Section Steel Beam

In this study, free vibration analysis of thin-walled channel section beam including warping effects has been carried out using Finite element method (FEM) and compared with experimentally measured results. Results reveal that natural frequencies of the system decrease on exclusion of warping in the analysis. Also, it has been observed that the difference between higher mode shapes were significantly high when theoretically obtained mode shapes considering warping and without warping were compared. Thereafter, the Modal Assurance Criterion (MAC) plot is presented to show the difference between the mode shapes with and without consideration of warping stiffness.