On the Basic Stability Equations fbr Beams with Thin-Walled Open Sections

The differential equations for the stability of a beam with a thin-walled open section are derived from the total potential energy of the beam in accordance with the variational principle. The main object of this study is to show the applicability of the concept of the initial stresses to the stability problems of the beams. By using exact initial stresses, including the transverse and warping shearing stresses, it is possible to derived mathematically the general stability differential equations and the correspoding boundary conditions. The same procedure used in this study can be applied to the more complicated problems in geometry, namely the stability of the curved and twisted beams