To find the buckling factor of safety of a frame under given loads, use pfbkelin.exe in conjunction with brun45.exe .
Documentation is in pfbk.txt .
The program takes into account inelastic action when the axial compressive stress exceeds one-half the yield point. An interaction equation describes the variation in the tangent modulus of elasticity. The effects of axial load are included in the second analysis and are used to form the geometric stiffness matrix for the buckling analysis. The results of the elastic analysis are given. Shear deformations are included.