Leopold II Tunnel: work progress

Group Me@BESIX Me@SixConstruct me@BELEMCO Me@Socogetra Me@Vanhout Me@BESIX Infra Me@Vandenberg Me@FrankiFoundations Me@JacquesDelens Me@Cobelba Global 2 min read

BESIX and its partners have taken advantage of the months of July and August - which mean school holidays in Western Europe - to carry out major work in the Leopold II Tunnel in Brussels. The 2,600 metres-long tunnel is a major traffic artery which links the western Belgian motorways to the capital’s city centre.

Works in July and August 2019

The renovation of the Leopold II Tunnel has begun in 2018, on behalf of the Brussels-Mobility regional public service. Works are carried out by the CIRCUL 2020 consortium, composed of BESIX, Jan De Nul and Engie-Fabricom.

However, only the months of July and August see the tunnel closed entirely, enabling work to be optimised and carried out 24/7. In the months from September to June, work is carried out in the tunnel exclusively at night, after 10 p.m., and the tunnel has to be operational from 6 a.m. in the morning. This is also the site’s most significant logistical challenge.

"July and August have been an intensive two months. They've enabled us to complete large-scale projects, some of which would have been impossible for the rest of the year because of the traffic during the day. Our teams were working seven days out of the seven and 24 hours out of the 24. They accomplished fantastic work," says Bram Vandewalle, Project Manager.

The most important activity for the 2019 summer holiday period was to demolish and relay 50% of the roadway. In addition, all the sewage pipes were updated and the pavements, containing some kilometres of conduit pipes and a special water main for firefighting, were modernised on both sides of the road. The team also took advantage of the complete closure of the tunnel to make significant progress with the renovations to the tunnel’s ceilings. Not only did the concrete have to be repaired and a waterproof coating applied, but a fire-resistant cover also had to be put in place. Major civil engineering works were also carried out for the construction of new emergency exits and technical areas. When the tunnel re-opened on 2 September 2019, three new emergency exits came into service, which means that several existing emergency exits can be tackled in the next renovation phase. Several major pieces of technical equipment were renewed, including high-voltage installations, transformers and extractors.

Bram Vandewalle: "This work is also a great example of one-stop-shop collaboration within the Group. The main sub-contractor for the site all through these two months was BESIX Infra (BESIX's entity specialised in road construction). Van den Berg (BESIX's entity specialised in cables and pipelines) also played a role, notably in installing several kilometres of conduits for the technical installations in the pavements. To each his own speciality!"

Daunting challenges

Opening the tunnel to traffic from September to June isn't the only challenge that the site faces. Far from it. Along this 2,600-metre stretch, the tunnel passes under the Brussels-Charleroi Canal, criss-crosses underground railway stations and metro lines, water pipes and the municipal sewage network. On the surface above, densely built-up areas give way to the classified Elisabeth Park, with the Koekelberg Basilica close by.

Bram Vandewalle: "Everything we do in the tunnel and outside - the emergency exits, for example - takes a broad range of specific constraints into account. These are major challenges, which make the site all the trickier ... and all the more interesting".