Some Remarks on Perceived Safety with Regards to the Optimal Safety of Structures

This paper gives a critical view about the development and application of optimisation procedures for the safety of structures. Optimisation techniques for the safety of structures have experienced major progress over the last decade based on, for example, the introduction of quality of life parameters in engineering. Nevertheless such models still incorporate many major assumptions about the behaviour of humans and societies. Some of these assumptions and limitations are mentioned briefly in this paper. These assumptions heavily influence the outcome of such optimisation investigations and can not be neglected in realistic scenarios. Therefore, the authors advise against the application of such optimisation techniques under real world conditions. An alternative for such optimisation procedures can be seen in the concept of integral risk management. Finally examples are given to illustrate effects of individual and social behaviour under stressed situations, which are not considered in the optimisation techniques mentioned. These effects are potentially considered within the concepts of integral risk management.