Experimental study on residual stresses distribution on small welded I-shaped section

In order to investigate the residual stresses of small welded I-shaped sections, an experimental program including eighteen sections, which were cut from a zipper frame after the shaking table test, was conducted by using the sectioning method. Based on the test data, the residual stress distribution and the magnitudes of these specimens were obtained, and the effect of the width-to-thickness ratio on the residual stress was studied. The results show that the residual stresses are not directly related to the width-to-thickness ratio. It is suggested that the value of the compressive residual stresses are 0.5 f_y (f_y is yield strength of steel) for the end of flange and the middle of web, and the tensile residual stresses are 0.8 f_y for the middle of flange and the end of web. Based on these results, the residual stress distribution model for small welded I-shaped sections was established and compared with the test results. The comparison result shows that most of the test residual stresses fall within the envelope of the residual stress distribution model.