Handling uncertainties in the seismic analysis using fuzzy theory

This study deals with the handling of uncertainties in the seismic analysis of complex structures. As a case example of a complex structure, a long span suspension bridge is considered, whose main span is 3300 m long. This is, without doubt, a very complex structure for the nonlinearities, uncertainties and interactions involved in its behavior. This paper focuses the attention on the definition of the seismic input (artificial accelerograms) and the consequent dynamical analyses which are developed in presence of uncertainties. In order to treat these uncertainties, an analysis is developed based on the fuzzy theory. Therefore, the procedure performed in order to reproduce the fuzzy response of the bridge is illustrated.