A new method based on the theory of fuzzy sets for obtaining an indication of risk

This paper concludes that traditional methods used in risk analysis have to be modified for adaption to the civil engineering industry. The main reason is that civil engineering systems are humanistic systems while traditional methods have been developed for mechanical systems. Consequently, the proposed method, indication of risk, is based on traditional methods such as fault tree analysis but modified according to the needs of the civil engineering industry. For humanistic systems, the method is based on the theories of possibility and fuzzy sets instead of the traditional theory of probability. The method is intended to be used to identify critical phases of the analysed systems and for optimizing system control. The method presented is exemplified by a risk analysis of a computer calculation. It is concluded that the method fulfils its intentions and deserves to be developed and examined further.