Buckling profile on thin walled steel column

Thin-walled steel sections are usually fabricated with flat plates which are welded along the connection between the plates. Hence, this process of welding can extremely introduce geometric imperfection and residual stresses which can affect the structural behaviour of a loaded thin walled steel structure. This paper presents an experimental study on the buckling profile of thin-walled steel tube columns due to welding. A measuring of buckling profile has been developed with ziq zaq method using a Web Deflection Transducer Bar on six thin-walled columns. This investigation consists of two different weld patterns. Three of which are with full weld and the remaining are with intermittent weld. The patterns of buckling profile due to welding were measured and the results are presented in this paper.