Stability and load-carrying capacity of thin-walled orthotropic poles of regular polygonal cross-section subject to combined load

Analysis of stability and load-carrying capacity of thin-wall orthotropic poles (columns, beams, masts, shafts) is conducted in the paper. The pole cross-section is a regular polygon and it is subjected to combined loads (compression, bending or torsion). The problem of buckling (stability problem) is solved using the asymptotic method by Byskov and Hutchinson with taking into account the second order approximation. Correctness of the results concerning the stability problem (critical loads and buckling modes) are verified by means of the finite element method using the programme ANSYS 5.4. FEM is also used in order to calculate load-carrying capacities. Numerical results are presented in diagrams. On the basis of the results several conclusions and final remarks are derived.