Thermal buckling and vibration analysis of cold-formed steel sections

Abstract

The current work focuses on the thermal buckling and vibration behaviour of thin-walled structures. Finite strip method based on the Hermite interpolation function is used along with the classical plate theory to model cold-formed steel (CFS) sections with arbitrary shapes. CFS member is made of temperature-dependent material. After obtaining the coupling effect by considering both the effects of temperature-dependent material and thermal stress, the principle of minimum potential energy is applied to obtain the eigenvalue equation for thermal instability and vibration problem. After that, detailed parametric analyses are performed to show the effect of different thermal stress distributions on buckling and vibration behavior of CFS sections with varying lengths and lateral restraint locations ( h R = 0, h /4, h /2, 3 h /4, and h ). The maximum difference in critical buckling temperature (CBT) predicted according to different design manuals is about 10%. The comparison of frequency and CBT for all thermal stress distribution case showed that uniform distribution gives the lower limit results, while case D gives the upper limit results in local instability region. The critical temperature and frequency are decreased with increasing the member length for evaluated temperature conditions when the lateral restraint regions are increased ( h R >0).