Cerca nel sito per parola chiave

pubblicazioni - Presentazione

Current challenges of seismic numerical modelling for dams: some Italian experiences

pubblicazioni - Presentazione

Current challenges of seismic numerical modelling for dams: some Italian experiences

In questa presentazione viene descritto un metodo di analisi dinamica semplificato per la , per analizzare la risposta non lineare di diverse grandi dighe in calcestruzzo in Italia e ottenere le relative “Curve di Capacità”. il confronto di tali curve all’interno di un “portafoglio dighe” consente così di sviluppare “indici di rischio” semplificati per classificarne il rischio sismico relativo e consentire così l’allocazione ottimale delle risorse.

The dynamic FEM analysis is currently the most effective tool to simulate the seismic response of dams. However, as the seismic forces increase up to the level of intensity typically corresponding to MCE, the complexity of the models and the computation time increase dramatically, having to take into account the non-linear behaviour of both materials and interfaces (joints and pre-existing cracks). At the same time, the overall models uncertainty increases, which in combination with the lack of information on the real response of dams when subjected to strong earthquakes, makes models calibration and subsequent seismic analysis a very challenging, expensive and often impractical task.

To cope with that, RSE adopted and further developed, a simplified dynamic method – the Endurance Time Analysis method (ETA) – which allows drastic reductions of the computational effort, to analyze the non-linear response of several large concrete dams in Italy and to obtain their “capacity curves” ranging up to collapse. In such way, even if the overall model uncertainty is still not properly addressed and quantified, the comparison of such curves within the dams portfolio allowed to develop simplified “risk indexes” to rank their relevant seismic risk, so that resource allocation for safety assessment can be definitely optimized.

Progetti

Commenti