Experimental verification of a beam element for thin-walled beams with torsion, distortion, and shear lag

Beam-type elements based on the theories of Euler–Bernoulli, Timoshenko, and Vlasov are widely used in civil engineering. However, shell and solid finite elements are often used when the effects on normal stresses of either shear deformation or distortion are considered important. Numerically validated in an earlier study with finite element models for shell-type structures, the same one-dimensional finite element model is further developed in this study with a low number of degrees of freedom per node that includes all the structural mechanisms without using 3D finite element models. Laboratory testing of an instrumented steel box girder is conducted, to improve validation of the goodness of fit of the finite element model with real structural behavior. •Calculation of the resistant modes of sections (shear, torsion and distortion).•Improvement of the description of the new beam element by applying energetic methods.•Laboratory testing of an instrumented steel box girder.•Validation of fitting with a one-dimensional finite element of the real behavior.