Local formulation for elasto-plastic corotational thin-walled beams based on higher-order curvature terms

The paper deals with the derivation of a local elasto-plastic finite element formulation of three-dimensional corotational beams with arbitrary cross-section. Based on Bernoulli beam kinematics, an improved displacement field is constructed by inclusion of second-order terms of cross-section local rotations. The formulation captures both the Saint-Venant and warping torsional effects of open cross-sections. Numerical tests show that the inclusion of the second-order terms of the local bending curvatures gives more accurate and more efficient element that allows a significant reduction of the computational time.