Residual stress model of welded steel L-shaped and T- shaped sections

Steel special-shaped columns, incorporating L, T, or cross-shaped sections, have gained increasing application in modern multi-story and high-rise buildings owing to their benefits in optimizing space utilization and enhancing structural performance. However, the welding manufacturing process induces residual stresses in these steel special-shaped columns, which can adversely affect the stability of the column components. This study conducted experimental research on the residual stress distribution in L-shaped and T-shaped steel columns using the sectioning method, which reveals the residual stress distribution patterns in the two types of steel special-shaped columns. By comparing and analyzing the experimental results with the existing residual stress model for welded sections, a residual stress distribution model for welded L-shaped and T-shaped steel columns is proposed, which fulfills stress self-balanced and is validated through numerical simulation methods. Subsequently, the proposed residual stress distribution model was applied in the numerical analysis of buckling in steel special-shaped columns. The effectiveness and necessity of considering this residual stress distribution model into the stability analysis of steel special-shaped columns are demonstrated by comparing the results with column stability test. The proposed residual stress distribution model significantly enhances the numerical accuracy for steel specialshaped columns, providing a theoretical basis for the stability analysis of such columns.