Saint-Venant’s torsion of thin-walled nonhomogeneous open elliptical cross section

This paper deals with the Saint-Venant’s torsion of thin-walled isotropic nonhomogeneous open elliptical cross section whose shear modulus depends on one curvilinear coordinates which define cross-sectional area beam. The approximate solution problem is obtained by variational method. usual simplification assumptions are used to solve uniform bars cross-sections. An example illustrates application derived formulae shearing stress and torsional rigidity.