Red footbridge over the Venoge
The footbridge over the Venoge provides a connection between the municipalities of Ecublens and Denges. The first footbridge, dating back to 1865, was replaced in 2006 by a wooden footbridge which had to be replaced in 2022, after 16 years in use, due to the beams rotting.
The concept developed for the new footbridge is to install a single arched girder to create a long-lasting crossing of the Venoge, with a trough-shaped cross section to make each crossing an even in itself.
The footbridge is a single 2-meter wide girder with a span of 24.60 m. The dimensions are similar to those of the previous wooden footbridge, allowing the former abutments could be used. The implementation of a trough-shaped section served to reduce the slope for users from 28% to 12%.
The footbridge is made from UHPFRC, with a trough-shaped cross section of varying height in order to focus the material in the areas where it is strictly necessary. Using UHPFRC made it possible to narrow the sections and reduce the weight in order to pre-assemble the girder and position it using a truck-mounted crane. The footbridge is made from dyed-in-the-mass red UHPFRC, as the structure was initially called the red bridge due to the railings that were painted red.
The deck is prestressed in the longitudinal direction in order to limit the tensile forces in the UHPFRC during use. The deck is rigidly linked to the abutments, thereby avoiding the need for pavement joints and support devices and facilitating maintenance work.
And to ensure that every crossing is an event in itself in addition to the experience of the gravity linked to the ramps, there is a clear view over the Venoge thanks to the railings consisting solely of uprights. Nature thus becomes a part of the footbridge and the tree trunks are visually entwined with the uprights set into the footbridge. Similarly, perforations are planned for the center of the trough to create views and make the crossing special at every level. And to make the experience even more memorable, a little music would make all the difference: simply tap the uprights to hear the sound of a giant harp, some of the local residents have already composed their own melodies…