Viaduct of Ghent
When the “Agentschap Wegen en Verkeer” decided on the reconstruction of the B401, it was none too soon to give the viaduct also a good make-over. Both the road deck, the bridge joints as the waterproofing were renovated.
The viaduct of Ghent has a total length of 1.300 m, this results in a total jobsite surface of some 31.000 m2. Because the viaduct is such an important access road, a strict work schedule had to be followed.
The waterproofing works started on July 14 and had to be finished by September 12, whatever the weather or the delays it could cause.
Doing such a project on such short notice and partly during the construction holidays was a big challenge. Finding good solutions was therefore a necessity, certainly because of the time pressure.
Emmanuel Van Damme and Kristof Devolder from Aswebo testify : “Doing such a project on such short notice and partly during the construction holidays was a big challenge. Finding good solutions was therefore a necessity, certainly because of the time pressure. On other jobsites we already saw the advantages of levelling the concrete deck with asphalt. We just needed to find a way to apply the waterproofing as efficiently as possible. That is why we looked for a collaboration with a company that could apply the waterproofing with a machine. Asphalis turned out to be the best partner for this job. At the beginning the collaboration did not go smoothly, but once we got the hang of it, all went very well.”
With great means
At the peak of the jobsite, not less than 5 application machines were simultaneously at work : the Easy-Max® 1 and 3, the larger Mini-Max® 1 and 2, and the more robust Mac-Max® for the heavier work. Work was done with 4 machines simultaneously one after the other to apply the waterproofing on the bridge deck in record time. Often when various other works around were still in progress. All the details on the contrary were done by hand : storm drains, hidden joints, junction strips and upstands with concrete rim.
Special about this project is that the Derbigum® GC 4 membrane is not applied on a concrete deck but on a specific bituminous asphalt, specially made to this end. All irregularities of the old bridge deck had to be levelled, preferably via a technique that took as little as time as possible. The method developed by Aswebo has proven its use on several occasions already.
This application did provide the deck to have a strong adherence so the forces produced by the road traffic above could be withstood easily. The protection layer on the waterproofing was after all but a few centimetres thick.