There’s only one Stade de Lyon... Populous’ new stadium marries references to its rural location with strength and power
There can’t be many football stadiums in the world where the fans’ chants will have informed the structure’s section, but that’s clearly the case at Olympique Lyon’s new Stade des Lumières. Some stadia might have one kop but it’s here, uniquely, it has two. Even more notably they sing chants to each other over the pitch, creating a particularly intimidating experience for visiting teams. ‘The Virage Nord and Virage Sud, as they’re known, will each have a conductor and drummers’, explains Populous project architect Garry Reeves, ‘So it was important that the sightlines allowed all terraces on both sides to see them. We removed all the mid-level hospitality suites on the north and south sides and shifted the section. This not only gives the terraces a huge parabolic sweep down towards pitch level but also allows VIPs dispersing right or left to the suites an amazing view of the goal opposite through a slim concrete aperture – it’s really something.’
This must appeal to the stadium’s client, which, having filled its trophy cabinet, moved from the 40,500-seat stadium designed by Tony Garnier in 1918 to this state-of-the-art 59,000-seat replacement on the city’s eastern fringes in January. In France stadia are usually owned by the city, but in 2003 the team struck a deal with the local government to create its own €297 million private ground and training facility, as part of a wider €405 million mixed-use regeneration of a 38ha site. Reeves recalls that: ‘Populous was originally approached by the club with the request for “another Arsenal”, but we said we were far more concerned with designing something that arose from the unique conditions of the site’. Those were a large plot of arable land with a copse very near a lake that forms the main reservoir for the city. To maintain as much as possible of the site’s bucolic character the stadium was raised above a huge underground car park to hide nearly 2000 of its 6,500 parking spaces, with the remaining space to be laid out in parkland of reinforced grass and trees. Preservation of the copse to the east as part of the bus approach, and green esplanade alongside the city tram stop, also maintain this connection with the landscape. From the access promenade that runs around the lower tier of the stadium the impression is of one set in a sylvan landscape, says Reeves.
For the 54,000m2 stadium itself, however, formed of over 130,000m3 of concrete with a 7300t steel roof structure – both materials Garnier would have known well – those natural inferences are more metaphorical than physical. Trees and the shade that they provide inspired Populous’ huge ETFE stretched fabric roof. This extends up to 40m beyond the main structural line of the stadium bowl to form a canopy for the promenade area connecting the north and south access ramps. All around, tall trunk-like steels rise at angles out of the deck level to grab the canopy’s leading edge and hold the whole structure in tension as it undulates asymmetrically around the stadium ring. The resulting, slightly jarring elevation of concrete and massive planes of PVC has been likened to the other alien that recently landed in Lyon, Co-op Himmelblau’s Confluence Museum. From some angles, the resemblance seems uncanny.
The canopy does help to offset the sheer volume of concrete to the stadium bowl and its supporting structure. The massive walls of pre-cast concrete really define the building – something Reeves puts down to French Building Control’s demands for emergency egress, which differ significantly from those in the UK. Populous and contractor Vinci worked alongside French organisations Socotec and Veritas to navigate their way through the circulation, safety and technical standards. ‘In the UK egress is time-based whereas in France it is based on the factors of people numbers and stair width and it’s a critical difference,’ he explains. ‘Capacity here is similar to the Emirates stadium. There we have 48m total stair width to decant 60,000 people whereas here it’s 143m. They will both take around eight minutes to empty but the difference that latter figure makes to the final look of the building is significant.’ So more mass, basically. Within every 46m by 8m insitu cast core there are two pairs of scissor access stairs serving the bowl tiers, a fire stair for use only by emergency services and an additional VIP stair.
But, he goes on, access and egress are not the only reasons the cores are as big as they are. Not only were the loads of the roof enormous, requiring reinforced concrete walls, but Lyons, lying on the plane of the Alps, is subject to seismic activity, which the structure needed to take account of. This led to the decision to shutter and cast the whole lot. Pours were carried out using concrete batched on site, allowing any colour differences, if they occurred, only to manifest on a floor by floor basis, delineated by ‘baguette’ nylon sections fixed back to the formwork. By contrast, all the concrete in the stadium used concrete planks, obviating the need for acro jacks and saving programme time. Reeves explains the logistics are usually that two construction teams start at opposite sides of the stadium, work their way around in both directions and meet in the middle. Here four teams worked their way around to create the stadium from quadrants so in the end the bowl superstructure, cores and 12m high concourses were all constructed, using 11 tower cranes, in nine months.
For the conferencing and hospitality zones on the west and north sides of the stadium there was a desire to underplay the Lenoir structural glazing to allow the superstructure to be read through it. However, more seismic regulations meant the firm’s preferred mullion-free system had to be replaced with transoms and mullions, the latter on the inside face of the glass to reduce their effect. The horizontal runs at promenade level, with their bullnoses draw punters around the building but remain discreet, as the canopy above serves the main role of reducing solar gain on the glass. French guidance required fire truck access through the facade, accounting for the recessed blank aluminium openable panels that occur every 40m along the facade. Luckily Populous saw this requirement to mediate between the concrete and glass facades, so they appear, duly recessed, at their interfaces.
The roof, which dips down in front of the structure to create impact on the elevation, is a tri-partite structure, modifying in nature and material to serve three different purposes. On the inner leading edge, a clear polycarbonate roof reaches out over the pitch, allowing UV light through to support grass growth. Above the main stadium seating a Sarnafil roof takes over, fulfilling the waterproofing requirement. Above the promenade its 23,000m2 Serge Ferrari TX30 PVC composite material extending out to the steel columns. Specialist contractors used high frequency welding to bond together the 30m by 6m panels together, producing a tensile resistance of 11t/m2. Prestressing in both warp and weft gave it good dimensional stability. Serge Ferrari’s Francoise Fournier says the tension is key to the material’s performance, with a stretch of only 1-2% on any 30m long panel – to ensure it could deal with the necessary snow and wind loadings. Eyelets in the fabric edge are tied by marine cord to lacing tubes, which are in turn attached to the steel perimeter beam, with a gutter detail at the outer edge dealing with run-off. Two panels a day were installed – 144 in all – totalling three months’ work.
Programme and logistic savings both contributed to the fact that a project that would have taken 36 months to complete was finished in 29, with the inaugural match in January this year. By all accounts the two Virages are very happy with their new stadium, but perhaps the proof of the pudding will come when the stadium hosts one of this year’s Euro semi-finals, making the Stade de Lyon centre stage for millions, not thousands, of chants.