The influence of the fabrication process on the buckling of thin-walled steel box sections

• Published in: Thin-walled structures Vol. 40; no. 2; pp. 109 - 123
• Main Authors: Pircher, Martin, O'Shea, Martin D., Bridge, Russell Q.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2002; New York, NY Elsevier Science
• Subjects: Applied sciences; Axial load capacity; Buckling; Computational techniques; Condensed matter: structure, mechanical and thermal properties; Deformation and plasticity (including yield, ductility, and superplasticity); Design; Elasticity. Plasticity; Exact sciences and technology; Fatigue, brittleness, fracture, and cracks; Geometric imperfections; Mathematical methods in physics; Mechanical and acoustical properties of condensed matter; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Mechanical properties of solids; Metals. Metallurgy; Physics; Residual stresses; Steel; Strength; Thin-walled box sections; Welding; Design; Thin-walled box sections; Geometric imperfections; Welding; Axial load capacity; Residual stresses; Steel; Buckling; Strength; Geometrical shape; Mechanical strength; Form defect; Displacement(deformation); Numerical method; Experimental study; Wedge; Finite element method; Welded joints; Modelling; Thin walled beam; Steels; Strength of materials; Flat plate; Production process
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/S0263-8231(01)00055-6

Steel box sections are usually fabricated from flat plates which are welded at the corners. The welding process can introduce residual stresses and geometric imperfections into the sections which can influence their strength. For some thin-walled sections, large periodic geometric imperfections have been observed in manufactured sections. Subsequent investigations have indicated that the imperfections are in fact buckling deformations i.e. the box section has buckled due to welding residual stresses prior to any application of external load. The welding procedure and the behaviour of the box sections under load has been modelled using a finite element analysis that accounts for both geometric and material non-linearities. Tests have been carried out on box sections with a range of width to thickness ratios for the plate elements. Modelling has been shown to give good correlation with the test results. The conditions for buckling to take place as a result of the welding process have been established. A design method has been proposed.