Discover the commitments behind the Canal
Find here the structural commitments of the Société du Canal Seine-Nord Europe and the project partners.
Discover the commitments behind the Canal
Find here the structural commitments of the Société du Canal Seine-Nord Europe and the project partners.
Among the works currently under construction, the RD40bis bridge which will cross the Oise lateral canal, widened and deepened to become the Seine-Nord Europe Canal at Pimprez, is making great strides! At the start of summer 2024, the metal frame of the bridge was put in place by launching. What does this consist of? Explanations.
This technique allows the bridge structure to be built in the immediate vicinity, on a temporary platform behind an abutment , and then put in place while minimizing disruption to traffic (in this case, river traffic) . The launching process involves moving the structure from its temporary position to its final position. See the operation in action frame by frame in the time-lapse video below.
In the case of the RD40bis bridge, the metal framework was assembled on site , behind the southern abutment of the structure. It was equipped with a specific device consisting of a system of cables and pulleys fixed to the deck and operated by winches positioned on the launching platform.
During the preparation phase for its installation, the structure was placed on temporary supports made of a Teflon plate.
A temporary 49-meter bowsprit (red section) has been added. This, made of lighter metal beams than the final beams, has been installed at the front of the bridge deck to facilitate its horizontal movement to its final position and allow it to berth on the supports.
Once these elements were in place, the 78-meter-long, nearly 320-tonne framework was pushed using a winch and pulleys . As it advanced, counterweights were placed at the rear of the framework to keep it balanced before the cutwater reached the opposite abutment.
The frame is placed on Teflon plates because a low-adhesion surface is needed to allow the structure to slide horizontally. To help with this, soap is used to lubricate the structure and thus facilitate its movement!
