Earthquake structural retrofitting of electric power networks under economic constraints

This paper presents a procedure to individuate the optimal retrofitting strategy for electric power networks (EPN) subjected to seismic events. The optimization consists in the minimization, under economic constraints, of the probability of power cut-off at the nodes where electric energy is most needed in the post-earthquake situation; these ones will be referred to as critical nodes. The model of EPN used herein has been already presented |I.Vanzi (1996), I.Vanzi (2000)] and is briefly recalled in the text. The method to individuate the critical nodes, based upon the value of an index herein proposed, is first illustrated; then the optimization procedure for the choice of the elements of the EPN to upgrade is examined, based upon a standard reliability study. Its effectiveness is tested on an existing EPN, the one of Sicily in Italy; it is shown that the optimization procedure is effective and may lead to a significant saving of economic resources.