Multi-criteria Decision Making for Seismic Retrofitting of an Underdesigned Rc Structure

Seismic retrofitting of under-designed structures is a consolidated approach to risk management. Several options are available for the achievement of the vulnerability reduction goals, each of those having peculiar performances in respect of different technical and non-structural criteria. Selection of the best solution is a non-trivial task, because criteria may conflict each other. MultiCriteria Decision Making (MCDM) methods may be useful in the matter, allowing to rank the overall performances for the set of alternatives and, therefore, to identify the optimal one. In the study presented herein, such approach was applied to the seismic upgrade of an old type RC building, hypothesizing an update of the seismic hazard at the site where the structure is supposed to be located. Four different strategies were designed to get the required seismic performance. Non-linear structural modeling, seismic risk analysis, criteria selection and MCDM results are also discussed.