A UNIFIED COMPUTATIONAL STABILITY CONCEPT FOR CONSERVATIVE AND NONCONSERVATIVE SHELL RESPONSES

The present contribution is concerned with dynamic stability investiga tions of structural responses. Special attention is given to a finite rotation shell theory, its numerical finite element implementation inv olving elasto-plastic material behaviour, and to computational procedu res for the tracing of arbitrary response paths. Occurring instability phenomena can be treated with the help of a fundamental stability con cept: Lyapunow exponents quantitatively decide upon local stability pr operties of fundamental responses. For the characterization of kinetic instability phenomena, such as parametric resonances, flutter, dynami c quasi-bifurcations, or kinetic snap-through behaviour, special class es of qualitative techniques for neighbouring orbits are considered. ( C) 1997 Civil-Comp Ltd and Elsevier Science Ltd.