One Approach to the Nonlinear Behaviour of Thin Walled Beams with Symmetrical Open Sections

Abstract

The principle of virtual work is applied to thin walled beams with a cross section having their middle line of an arbitrary curvilinear shape and with continuously varying thickness. Six equilibrium equations and a seventh one relating the constrained torsion are derived taking into account the general sectorial coordinates. The obtained relations are applied to the turbine blade shaped elements with one plane of symmetry. All necessary geometrical characteristiques are calculated for one element of the modified cross section shape and it is shown that it is not recommendable to neglect the influence of those secondary effects.