Raising of the bridges on the Albert Canal_Hermalle bridge

The Albert Canal is the most important waterway in Belgium and Wallonia. Flanders is carrying out work to remove bottlenecks and modernise the network. Flanders proceeds with the widening of the canal between Antwerp and Wijnegem and the raising of around thirty bridges between Antwerp and Wallonia to ensure a clearance height of 9.10 metres. This will allow vessels to carry four layers of containers instead of three.

This project is a continuation of this connection between the Walloon hinterland and Antwerp with the same gauge. This specifically concerns the developments at the Hermalle-sous-Argenteau bridge, but similar studies are being carried out by the same project author for the Haccourt, Lixhe and Lanaye bridges in the municipalities of Oupeye and Visé.

The Hermalle bridge is a bowstring structure with a span of 138 metres, built in 1981. It has a composite steel-concrete deck. On either side of the bowstring bridge, the deck extends into a composite twin-girder bridge with a 22.5-metre approach span.

The bridge must be raised by 1.75 metres to clear the desired 9.1-metre clearance. This operation is carried out using telescoping towers specifically adapted for this purpose. The piles and abutments of the structure will need to be raised/adapted accordingly.

Taking advantage of this raising work, specific maintenance operations will be carried out on the structure, namely:

• Replacing expansion joints,
• Anti-corrosion repainting of the entire frame,
• Laying new surfacing on roads and pavements.

Furthermore, raising the structure will obviously require the redevelopment of the roads/ramps connecting to it. The slopes encountered inevitably reach values close to 7% over several dozen metres. These slopes are acceptable for road traffic but are not really suitable for comfortable cycling/PRM access. However, a major cycle network comprising a RAVeL and several “node” connections passes over the Hermalle bridge. The presence of a proper cycle path on the bridge is therefore essential to enable the RAVeL arriving on the left bank upstream of the canal to cross the bridge and then join the left bank of the Meuse. To meet this need, the selected project involves widening the bridge on its upstream side to incorporate a two-way cycle path connected to a development on SPW land, in order to build ramps closer to 5% over a width of 4 metres. On the right bank, this cycle path requires the construction of an underpass beneath the access ramp to the bridge in order to connect to the existing RAVeL network.
On the left bank, the soft mobility route loops around the SPW site and gently slopes down to the road on the quay, where a safe crossing will be built to connect to the RAVeL path running alongside the canal.