In the battle to be best, it seems size really does matter.
Sometimes, however, it isn’t appropriate or possible for the whole building to be bigger or taller than a rival, so designers are now looking at individual components.
In speaking about the possibility of a mile-high skyscraper, Council of Tall Buildings and Urban Habitat chairman Timothy Johnson said it is human nature to want to build higher. Why wouldn’t a designer or engineer want to push the boundaries and push themselves to find out just what is possible?
The new roof for Singapore’s National Stadium, orchestrated by engineering firm Arup, is certainly ambitious. Once it is delivered, it will likely be hard to argue against what promises to be a massive technical achievement.
Part of the $1.33 billion Singapore Sports Hub (SSH) in Kallang, the new steel roof of the 55,000-seat centrepiece is set to boast the largest dome in the world.
“We designed the stadium as an elegant dome spanning 312 metres – that’s close to four A380 airplanes parked wing to wing,” said Clive Lewis, design leader for the project. ” Not only is it wide, the ultra-thin shell roof structure is also very efficient and uses minimum materials for construction.”
Weighing 8,057 metric tonnes with an area of 20,000 square metres, it will be 35 metres wider than the current biggest at the Dallas Cowboys Stadium in the US.
“All along, the challenge (for us) is the roof structure,” said Chen Shee Shann, contract director for stadium builder Dragages. “We awarded the contract for the steel roof structure early last year and by November or December we got all the materials in and started fabrication. That part of the risk is already over, now it’s getting the work done.”
The ultra-thin structure addresses the issue of spectator comfort in the tropics and can be fully opened or closed in 25 minutes. The clever design also provides shade during events and an innovative energy-efficient spectator cooling system that delivers cooled air to every seat in the stadium. These pockets of cooled air will reduce energy use significantly, compared to a more conventional overhead cooling system.
“We wanted to keep the rain and heat out, but we also wanted it to be an open and dynamic space,” Lewis said. “After extensive research into comfort expectations and energy in use, we realised that a naturally ventilated stadium with localised cooling gave us the best solution for the local climate in Singapore. By incorporating a moving roof, the stadium will be further protected from the harsh climatic conditions, allowing events to be hosted during the hottest parts of the day.”
Versatility is a key component of the stadium design. By integrating moving tiers, palletised turf modules and a fully closing roof, the stadium can accommodate a wide calendar of sporting events like football, athletics and cricket without compromising on the proximity and quality of view for spectators.
The largest sports infrastructure Public Private Partnership project in the world, the project is now undergoing construction and is expected to be ready by April 2014.