An. Kounadis et al., An improved energy criterion for dynamic buckling of imperfection sensitive nonconservative systems, INT J SOL S, 38(42-43), 2001, pp. 7487-7500
Imperfection sensitive, multi-degree-of-freedom, autonomous, structural sys
tems under partial follower compressive loading, which lose their stability
via divergence are investigated both qualitatively and quantitatively. Att
ention is focused on the global instability of that equilibrium state on th
e locally stable primary path, which at a certain level of the loading beco
mes globally unstable. Previous work valid for potential systems under step
loading is extended here to nonpotential, imperfection sensitive systems.
The serious difficulty of the lack of potential of the follower type of loa
ding is overcome by formulating an appropriate energy balance equation, inc
luding loss of energy. Then, similar considerations to those for potential
systems can be established, and geometric criteria can be formulated for an
"equivalent energy" surface. Using the mean-value theorem for integrals on
e can obtain approximate dynamic buckling loads that are very good for stru
ctural design purposes. The efficiency and reliability of the proposed meth
od is comprehensively demonstrated through numerous examples. (C) 2001 Else
vier Science Ltd. All rights reserved.