An innovative lifting system based on an Enerpac gantry and turntable is enabling the rapid renewal of the important Souverains railway viaduct in central Paris. Developed by Bouygues Travaux Publics Régions France and deployed by heavy lifting company Mediaco Heavy Lift, the Léonard lifting system has replaced the bridge decks supporting 13 railway tracks used by around 1,600 trains every day.
Built in 1868, the ageing Souverains viaduct’s 25 bridge decks have been replaced to ensure the safety, reliability and performance of the Paris region’s rail network for many years to come. In order to minimise disruption to rail traffic, the viaduct decks were removed and replaced over a period of nine months. Given the need to keep the overhead power lines in place, Bouygues Travaux Publics developed an innovative rail lifting device called ‘Léonard’, which allowed the bridge decks to be replaced from below.
Mounted on RER C tracks in the viaduct tunnel, the Léonard lifting system comprises an Enerpac SL200 hydraulic gantry supporting a steel platform on which an Enerpac ETT400 turntable is positioned. The gantry lifts and lowers the platform synchronously, ensuring that it always remains level.
Precise replacement of a viaduct deck
During the May and August bank holidays, the bridge decks were systematically removed and replaced by Mediaco Heavy Lift. The new concrete decks are 9.33 m long and 3.74 m wide, and weigh between 28 and 52 tonnes.
The old decks were first demolished. Outside the tunnel, a new bridge deck is placed on the Enerpac turntable. The Leonard was then moved along the tunnel rails to the correct position and the SL200 gantry platform raised, lifting the bridge deck above the girders. As the new deck is perpendicular to the track, it was rotated using the Enerpac ETT400 turntable to align it with the rail tracks and other decks.
The final positioning of the deck was achieved by moving the Léonard lifting system back and forth. The X adjustment was made by moving the SL200 hydraulic gantry. The Y adjustment is made using Mediaco Heavy Lift’s 50 T skidding system.
“The development of the Léonard rail lifting system based on our Enerpac SL200 gantry and ETT400 turntable enabled us to complete the work on schedule while ensuring the highest possible level of operational safety. It is a perfect solution for this ambitious project,” said the head of engineering and design at Mediaco Heavy Lift.
At the beginning of August, the last 14 deck sections were installed using the Léonard for the inner decks and a crane for the outer decks. The complete renovation of the Souverains railway viaduct is scheduled for completion in November 2025.
For more information on Enerpac heavy lifting systems, please visit www.enerpac.com.
For more information on Mediaco Heavy Lift, please visit www.mediaco.fr.
–
