The Bridge over the Magra river, also known as the Bridge of Caprigliola, was a long road bridge on the Italian State Highway SS330 that for 111 years connected the two municipalities of Caprigliola and Albiano di Magra, in Tuscany. On the morning of 8 April 2020, the structure collapsed on its entire length, with a “domino” effect. Only two people were involved but fortunately they managed to leave the vehicles and survived. The bridge was designed at the beginning of the Twentieth Century by the engineer Attilio Muggia, one of the pioneer of reinforced concrete in Italy. Once completed in 1908, the structure was one of the longest RC bridge in the world. Five arches of 51 m, resting on four masonry piers linked the two banks of the Magra river. The bridge was destroyed by Germans during II World War and then rebuilt in 1949 with a new design inspired by the works of the Swiss engineer Robert Maillart. This thesis work aims to reminisce the bridge’s history in all its main phases, describing also the Italian background regarding reinforced concrete arch bridges and their post-war reconstruction. Possible collapse causes and critical aspects of the structure are analyzed through an extensive modelling campaign. Several macro and micro-models of the bridge were developed in order to study its structural behaviour and potential inadequacies. In the end, significant conclusions are illustrated and discussed, as well as possible future investigations.
Il collasso del Ponte sul fiume Magra: analisi delle cause e dei meccanismi di rottura attraverso la ricostruzione storica e lo sviluppo di modelli. Il Ponte sul fiume Magra, noto anche come Ponte di Caprigliola, era un ponte stradale sulla Statale SP70 che per 111 anni ha collegato i due comuni di Caprigliola ed Albiano di Magra, in Toscana. La mattina dell'8 aprile 2020 la struttura è crollata per intero con un effetto “domino”. Solo due persone sono state coinvolte ma fortunatamente sono riuscite ad abbandonare i veicoli e salvarsi. Il ponte è stato progettato all'inizio del Novecento dall'ingegner Attilio Muggia, uno dei pionieri del cemento armato in Italia. Una volta completata nel 1908, la struttura era uno dei ponti in cemento armato più lunghi del mondo. Cinque archi di 51 m, poggianti su quattro pile in muratura univano le due sponde del fiume Magra. Il ponte fu distrutto dai Tedeschi durante la Seconda Guerra Mondiale e poi ricostruito nel 1949 con un nuovo progetto ispirato ai lavori dell'ingegnere svizzero Robert Maillart. Questo lavoro di tesi intende ripercorrere la storia del ponte in tutte le sue fasi principali, descrivendo anche il contesto italiano dei ponti ad arco in cemento armato e della loro ricostruzione postbellica. Possibili cause del collasso e criticità della struttura vengono analizzate attraverso un'ampia campagna di modellazione. Sono stati sviluppati diversi macro e micro-modelli del ponte al fine di studiarne il comportamento strutturale e le potenziali inadeguatezze. Infine, vengono illustrate e discusse parziali conclusioni e possibili indagini future
The Bridge over the Magra river: analysis of collapse mechanisms and causes through historical reconstruction and models development
SALOMONE, ROBERTO
2019/2020
Abstract
The Bridge over the Magra river, also known as the Bridge of Caprigliola, was a long road bridge on the Italian State Highway SS330 that for 111 years connected the two municipalities of Caprigliola and Albiano di Magra, in Tuscany. On the morning of 8 April 2020, the structure collapsed on its entire length, with a “domino” effect. Only two people were involved but fortunately they managed to leave the vehicles and survived. The bridge was designed at the beginning of the Twentieth Century by the engineer Attilio Muggia, one of the pioneer of reinforced concrete in Italy. Once completed in 1908, the structure was one of the longest RC bridge in the world. Five arches of 51 m, resting on four masonry piers linked the two banks of the Magra river. The bridge was destroyed by Germans during II World War and then rebuilt in 1949 with a new design inspired by the works of the Swiss engineer Robert Maillart. This thesis work aims to reminisce the bridge’s history in all its main phases, describing also the Italian background regarding reinforced concrete arch bridges and their post-war reconstruction. Possible collapse causes and critical aspects of the structure are analyzed through an extensive modelling campaign. Several macro and micro-models of the bridge were developed in order to study its structural behaviour and potential inadequacies. In the end, significant conclusions are illustrated and discussed, as well as possible future investigations.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/12765