Residual stresses of 550 MPa high strength steel welded cruciform sections: Experimental and numerical study

Residual stresses significantly affect the buckling behavior of welding cruciform section column. In this study, an experimental study is presented to investigate the residual stresses distribution of 550 MPa high strength steel welded cruciform sections using the sectioning method. Four cruciform sections with different width-to-thickness ratios of plates are tested to analyze the magnitudes and the distribution zone of residual stresses. A three-dimensional finite element method is developed to the effects of the width-to-thickness ratios of plates on re-sidual stresses distribution. It is concluded that the compressive residual stresses at the center of plate ranges from 0.10 f(y) to 0.42f(y), and they decrease as the width-to-thickness ratios of plates increase. The width-to -thickness ratios of plates have no obvious influence on the tensile residual stresses. The effects of artificial error on the residual stresses are not obvious. All component plates satisfy the self-equilibrium conditions. A distribution model of residual stresses is suggested on the basis of experimental and numerical results, and a good agreement between the proposed distribution model and test data is made.