For many engineering structures loss of stability represents the most important failure mode. The progress of computer technology in the last decade enabled applications of methods based on Finite Elements for numerical predictions of the stability behavior, even for dynamci loading conditions. Although it is well known that under defined loading conditions especially geoemtrical imperfections often strongly influence the stability behavior, most of the structures currently analyzed with such techniques are considered as perfect. The geometrical imperfections, which arise during the manufacturing and construction of the structure, are usually of stochastic nature. They directly influence the reliability of the construction. This paper shows an extension of research activities to stochastic dynamic stability problems. Geometrical imperfections are interpreted as randomly distributed and spatially correlated deviations from a perfect structure. Mathematically they are covered by point discretized rnadom fields. Their influence on the stability behavior can be analyzed by standard methods of structural mechanics. Stochastic dynamic loading is investigated. Since the loading is time dependent, the top Lyapunov exponent of the system serves as stability criterion.
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