Liberty Bridge, Mestre-Venice
Electrification of the Ponte della Libertà Mestre-Venice, Italy
Ten months of construction works and 35,000 hours of night work were required to complete the mission entrusted by RFI to GCF: to rebuild the railway electric traction system on the Ponte della Libertà, strengthening it and making it more resilient to the aggressive phenomena typical of the lagoon environment. The bridge is the historic trans-lagoon link that, since 1845, has connected Venice with the mainland.
The innovative portals adopted and the many solutions implemented - during the design phase, in the selection of materials and in production processes - have contributed not only to better supporting the significant and growing rail traffic, but also to giving the bridge a new skyline, transforming its 2,500 metres into an ideal, sober and modern “rail carpet”, worthy of a city of art, canals and… bridges.
Project features
The works were developed through four operational phases.
A preliminary check-up, including a comprehensive set of experimental investigations, aimed at assessing the overall structural condition of the two parallel railway bridges.
Construction of the foundation blocks, following the replacement of 500 reinforced concrete slabs (800 kg each) connecting the two railway bridges, each consisting of approximately 10 m³ of RCK45 concrete, exposure class XS3.
Installation and testing of the new innovative portals, consisting of 7.60 m high “V”-shaped lattice structures (weighing 1,700 kg) supporting massive 18.60 m beams (1,850 kg each), each equipped with four hangers weighing over 100 kg. Owing to their size, these structures were designed to serve all four tracks with a single large “T” made of 4 tonnes of special steel.
Installation and tensioning of the new overhead lines. Using 216 modern “Omnia” type cantilevers, at the beginning of 2019 the site completed the tensioning of the four new contact lines with a total cross-section of 440 mm² and fully regulated conductors.
