A Theory of Torsional and Coupled Bending Torsional Waves in Thin-Walled Open Section Beams

Abstract

An appropriate torsion or coupled bending torsion theory is developed for the dynamic behavior of thin-walled open section beams. A new, more accurate set of governing equations is established which eliminate the short-wavelength defects of both the Saint-Venant and Timoshenko torsion theories. This theory, which includes warping and associated effects of longitudinal inertia and transverse shear deformation, while agreeing with previous theories for large wavelengths, leads to satisfactory finite wave velocities for short wavelengths and high frequencies. Dispersion and group velocity curves for wide-flanged and channel sections are displayed.