ABSTRACT
This chapter demonstrates that for massless non-conservative systems critical loads exist. For conservative systems the static stability is based on the equilibrium of all acting forces. The missing of nontrivial states of equilibrium for non-conservative systems changes the situation and the equilibrium of the energy is applied. The non-conservative massless Ziegler's column is analyzed using the "extra energy method". The multi-spring-hinged system is used to determine static stability limits of non-conservative tangential loaded columns. The Euler stability identifies for non-conservative systems with nontrivial states of equilibrium critical loads, which are, however, in most cases not the smallest ones. To compare the "energy method" with the "extra energy method", the massless Ziegler's column is investigated once more. The critical loads of massless non-conservative systems with nontrivial states of equilibrium published in the books of Pfluger, Leipholz, Petersen and in many other publications – analyzed by equilibrium conditions – are in general not the smallest critical loads of these systems.
