INTERACTIVE BUCKLING OF AN ELASTICALLY RESTRAINED TRUSS STRUCTURE

Interactive buckling of an elastically restrained truss structure is i nvestigated by using an improved version of the Byskov-Hutchinson pert urbation analysis. The mechanical model consists of two horizontal bea ms connected by rigid diagonals, whose out-of-plane displacements are prevented by a continuous distribution of linear springs. When the two horizontal beams are compressed, three buckling modes are possible: o ne overall in-plane mode and two local (lateral and torsional) modes w hich, for a particular choice of the geometry of the structure, may oc cur nearly simultaneously. Three nonlinear equilibrium equations are d erived in the amplitudes of the three buckling modes and solved numeri cally for given initial imperfections.