Analytical Method for thin-walled members in general bending and torsion

Abstract

The classical theory of thin-walled members has been applied extensively in practice. Since the theory was based on the assumption of no shear deformation, it is unable to reflect some of the important phenomena such as shear lag in structures. In mixed variational principles, both stresses and displacements are taken as variables, and they create equal possibilities to yield good results both in stresses and in displacement. Based on a mixed variational principle and introducing the co-ordinate functions in the cross-section, a mixed variational method has been presented.1 Following this method, the method of solution for thin-walled members of open cross-sections in general bending and torsion is derived in this paper. This method is more general than the classical one and can be applied to members with rows of openings. It can also be applied to problems involving tension, bending and torsion actions, and simple analytical solutions in closed form can be obtained. Both warping and shear lag phenomena can be dealt with. © 1988.