The gallery between two stretches of tunnels is exposed to rockfall. The concrete deck risked to be damaged by severe events.
To secure the bridge from rockfall energies up to 2300 kJ, a gallery roof construction was built above the street-stretch between the two tunnels. To reduce the risk further, the gallery-roof was secured by the ROCKFALL-X G damping system. A protection system which works by absorbing kinetic energy, thereby limiting deformation and above all limiting the pressure exerted on the deck by spreading loads over a wide area, while limiting the weight on the gallery so as not to overburden it.
556 preassembled ROCKFALL-X G big bags were delivered and installed during May and June 2014 in the following configuration: