This paper on "FEA for Optimum and Reliable Structures" was presented at the NAFEMS World Congress on Design, Simulation & Optimisation: Reliability & Applicability of Computational Methods - 9-11 April 1997, Stuttgart, Germany.

Abstract

For some years now, the optimization of structures have become more and more important due to the availability of automatic optimization procedures. It is typical for this type of analysis that the users have to have a profound knowledge about the structures and their loading in order to specify the optimization task as accurately as possible. Nevertheless, the loading is often applied by superposition of several loading cases and an additional margin of safety. Then the optimization will not cogently result in a reasonable and stable solution.
If we consider all the modeling parameters which are uncertain quantities, then it becomes very clear that this fact is never taken into account by usual optimization strategies. So, the reliability analysis can be used as a method to determine the influence of numerous uncertain model parameters and loading cases and to characterize the stability of the optimum found.
The paper presents the joint use of optimization and the stochastic reliability analysis by practical examples. This shows that the reliability analysis is a valuable extension of the optimization procedures in order to get optimum designed structures with optimum loading capacity.