ULTIMATE LOAD BEHAVIOR OF WELDED THIN-WALLED STUB COLUMNS UNDER COMBINED LOADING OF AXIAL-COMPRESSION AND BENDING

This paper describes a theoretical study on the post-buckling behaviour and ultimate strength of the welded thin-walled box-section and I-section stub columns under combined loading of axial compression and bending at the ends. A large-deflection elastic-plastic spline finite strip method associated with a more rigorous multi-layer integration is developed to analyse such a problem. Initial imperfections including the residual stresses and initial deflections of plate elements are considered. An iterative numerical procedure combining a modified arc-length method and Newton-Raphson iteration is presented to predict a complete load-deflection curve of the stub column. The analytic results obtained by the spline finite strip method is presented in the form of interactive diagrams for typical values of plate slenderness ratios. Comparison with the experimental results previously published is made and good agreement is obtained between both results [A. J. Davids and G. J. Hancock, J. Struct. Engng, ASCE 112,960-976 (1986)].