Elasto-Plastic, Flexural-Torsional Analysis of Thin-Walled Curved Beams

In this paper, elasto-plastic, flexural-torsional analysis of curved beams subjected to thrusts and bending moments applied in the plane of initial curvature is carried out by using Galerkin method. This method provides not only continuous distributions of stresses and displacements but also substantial cut of computing time compared with FEM because the size of final simultaneous equations could be considerably reduced.The results of elastic analysis (lateral buckling loads, deflections of beams) are in fairly good agreement with those of S. P. Timoshenko and V. Z. Vlasov. From the results of elastoplastic analysis, it is clarified that initial imperfections such as initial deflections and residual stresses due to welding result in considerable reduction of lateral-torsional buckling strength.The authors also suggest a simplified method to estimate elasto-plastic, lateral-torsional buckling load of curved beam with I-sections subjected to uniform bending.