Mentre nel campo elastico e in quello plastico le strutture geometricamente simili hanno lo stesso comportamento, quando si considerano il ramo discendente della curva sforzi-deformazioni e la localizzazione delle deformazioni, il comportamento strutturale passa da duttile a fragile semplicemente modificando le dimensioni e lasciando inalterata la forma geometrica. Si riscontra quindi come l'effetto scala abbia una importanza fondamentale sul comportamento strutturale globale delle strutture di calcestruzzo semplice ed armato. Tale fenomeno, previsto teoricamente è confermato dai risultati sperimentali finora ottenuti dagli autori e può influenzare diversi aspetti riguardanti il progetto delle strutture. Il presente lavoro mette in evidenza come l'effetto scala sia presente anche nelle travi di calcestruzzo armato aventi basso contenuto di acciaio e ne delinea le implicazioni sulla percentuale minima di armatura per tali strutture.
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Con il contributo del Ministero per i Beni e le Attività Culturali