Transforming Soccer City

More than a year after the start of the revamp of Soccer City in Johannesburg, the first contours of the main stadium for the 2010 World Cup are becoming visible

The columns that are constructed to carry
the roof were a real challenge to the engineers

All major construction projects confront a variety of issues. The challenges facing the 2010 FIFA World Cup range from strikes and corruption to enthusiasm that sometimes results in unrealistic plans. For some, this provides ammunition to point out the downsides of the tournament; after all, South Africa is still an emerging nation 14 years on from the first democratic elections.

But in what is reputedly the world’s most dangerous city, the construction of the main stadium for the FIFA 2010 World Cup event is progressing remarkably smoothly and steadily.

The centre of attention
The construction project is attracting a lot of attention. Stan Aarts, a technical manager who works on the project on behalf of Dutch company Interbeton, says: “If we want to, we can be busy with tours and media visits on a daily basis. There are always people interested in the project – particularly one of this magnitude. Many things happening here have never been seen before and have never been tested before in South Africa, like the extension of the pillars that will carry the stands.”

Interbeton is working in partnership with South African construction firm Grinaker-LTA. The company brings in international expertise as it has been involved in other stadium construction projects before, including stadiums for the 2006 FIFA World Cup event in Germany. To be able to cope with the increase in attention, the stadium is busy building a media centre as part of a bigger plan.

“We are currently also constructing a centre where we can start selling the corporate suites,” says project manager Mike Moody of Grinaker-LTA. “We expect by June 2008 to have a management company appointed that will run the stadium. To allow them to sell the hospitality suites a sample suite will be created where buyers can see what they will look like and decide on the finishes.”

Working through power cuts
Construction has been progressing steadily. “So far we haven’t really had much delay,” Aarts says. His statement comes as a surprise as South Africa has been hampered by power failures since the beginning of this year. The national electricity company Eskom can no longer cope with the demand. “This has not hit us directly as we have invested in generators. We have managed to continue the construction process. However we might feel the effect soon as suppliers have been affected by the lack of electricity. This will also affect the price for supplies.”

The power cuts have affected production all over the country, resulting in delays and price hikes due to increases in prices for raw materials. For Aarts and his team this also means more pressure on getting the supplies in on time. “We scramble to get our supplies and sometimes it is a competition with other stadiums or other industries. We simply cannot afford to be finished later than scheduled.” Aarts therefore regularly consults with the teams at the other stadiums currently being built to avoid competition for parts and supplies negatively affecting the construction process.

The biggest stadium in the South
Although the stadium in Johannesburg is being regarded as a revamp, it almost comes close to the building of a complete new venue. The cladding of the existing main stand has been removed; so has the roof. A major part from the stands has also been demolished and replaced. Aarts says: “The existing stands did not meet the FIFA requirements for sight-lines. We therefore had to replace the stands on the ground floor which was not much of an issue as they were constructed on an embankment. The existing first tier on the main stand was however more of a challenge. Here we decided to increase the length of the pillars that were carrying the main stand. By making them higher we managed to meet the requirements for the correct angle for the sightlines.”

Eight big tower cranes, including two imported from The Netherlands continuously transport new supplies and elements in place. “We have 27 months from the moment we started until the date of completion. Currently we have 1700 people on site. This will further increase to 3500 once we get closer to the deadline.”

Soccer City, as the stadium is officially named, will now finally get a tier all around the stadium as it was supposed to have from the beginning. This will make the stadium the biggest venue in the Southern hemisphere. “Once the stadium is finished it will have a capacity of 94,000 spectators,” Aarts says.

Rigid roof structure
Once Soccer City is finished it will resemble a calabash, a typical African pot that can be found all over the continent. Architect Bob van Bebber says it was important for the organising committee that the event would be an African event. According to the architect, Danny Jordaan, once the design was presented, the CEO of the organising committee chose it immediately.

Realising the ideas of architects is the challenge for engineers. “Engineers prefer straight lines where architects tend to have a preference for shapes,” Aarts remarks. “We had to make new inventions to be able to build the shaped columns that eventually will carry the cladding, as the architects designed columns that were canterleaving. Both the architects and the engineers had to make consessions to achieve this.”

Materials for the 2010 stadiums have been chosen on the principle that they are cheap and widely available. Many of the concrete elements are made on-site where a batch plant allows for mixing concrete according to requirements.

“We are not going to do anything fancy,” van Bebber has stated. “Our budget is tight and it is important for us that materials have been tested and proven.” To create a resemblance to a calabash without using expensive materials, fibre cement panels will be used for the cladding. Aarts explains: “These panels are widely available in South Africa and they came very close to what the architect had in mind.”

Each panel will weigh 15kg per sq m. In the cladding, eight windows will face in the direction of the other hosting cities; Cape Town, Port Elizabeth, Durban, Bloemfontein, Nelspruit, Pretoria, Rustenburg and Pietersburg. A ninth window will face towards Germany, host of the FIFA 2006 World Cup event.

The roof of the stadium will be constructed with light fabric that has been proven elsewhere. Nevertheless Aarts still faces a challenge. “The construction that will carry the roof will eventually have to carry a huge load. It will all come from the back of the stand and, due to the dimension and shape of the stadium, it will cover a huge length.”

To assemble the roof a special crane has been built in Germany which is due to arrive in June. The roof will only cover spectators seated in the hospitality suites and above. Although the fabric material does not really weigh much, the roof will also carry the lighting and sound system as well as two television screens which will measure nine by 26 metres.

“Floodlights can weigh up to 13kg each and, with dozens required to provide enough illumination, the effect of flood lights on roof design can be enormous,” says Malcolm Schütte of Philips Lighting in South Africa. “The stadium will get a ring of fire, like the Olympic Stadium in Berlin had in 2006.”

Mounting the lights beneath the roof canopy ensures that the light only illuminates the field and will have a lesser impact on the environment. Soccer City is situated on the outskirts of the city in an area that is expected to be developed with a golf course and an expansion of NASREC, South Africa’s biggest convention centre. Extensive illumination would have too much of a negative impact on the environment.

Perfect sonic experience
Once completed the stadium will, in every way, offer the perfect visitor experience. A digital sound system is also envisioned. Although Soccer City will remain a football-specific stadium, it is expected that it will also be used for concerts or political rallies. “Two tunnels will allow trucks to enter the field from the one side and leave from the other side to build stages,” Aarts says. To ensure optimum sound quality the best system possible is sourced. Technical director of Prosound Mark Malherbe explains the process of system selection. “If only speech is required, the system can be fairly straight forward. But when music is also needed, than there are greater requirements.”

Soccer City will opt for a digital system that allows the stadium to be divided into sound zones, each with individual control. This is important particularly when one wants to have a good quality sound in a stadium which is not sold-out, a scenario that can be expected post 2010.

“Each crowd is different. A football crowd tends to congregate around the goal. Managing the sound system therefore is more of a science,” says Malherbe. The quality and intelligbility of speech is affected by the time sound takes to die away, the reverberation time and the ambient noise in a sports facility. The reverberation time depends on the physical structure of a stadium and the number of spectators. An empty stadium has a much longer reverberation time as spectators absorb sound.

Selecting a proper sound system is also important as Soccer City will have two rings with corporate suites included. The construction of hospitality suites in the middle layer of the stadium influences the quality of sound. The use of a digital signal processor is therefore required as this will allow for a “sound delay”.

“When hospitality suites are located in a middle layer under the upper tier overhang, the sound is affected by an ‘audio shadow’. Additional units must therefore be installed so that sound can be received from two paths and out of phase,” Malherbe says. The delay is introduced between the main sound system and local sound systems to co-ordinate the two sources.

Self-sufficient power supply
With the flood lights and sound system being placed in the canopy, much force will be excercised on the roof structure. The designers have therefore sourced a steel structure that will be manufacturered in Italy.

Aarts explains the challenges he faces. “Once again it is first a matter of finding the quality material that you are looking for, but secondly we also need to have it arriving here in time.” Transport will be the next crucial element. For many nations, transport is less of an issue, but the South African ports of Cape Town and Durban hardly can cope with the increasing capacities. This subsequently results in delays that even can take as long as several weeks, particularly as the 700km road network from Durban to Johannesburg has been seriously affected by congestion and poor quality maintenance.

Aarts feels that a small delay can be overcome, but budgets, schedules and planning are tight. Since the Rand, the national currency, made a significant drop at the beginning of 2008 due to a weak US Dollar and the negative impact of load shedding on the economy, price increases of equipment and supplies sourced overseas will have a significant impact on the budget. Finance minister Trevor Manuel has therefore allocated extra budget to the event.

The show must go on
While the load shedding does not affect the construction process of the stadium, many believe that FIFA still might decide to move the event away as a blackout on match day would be unbearable. But Aarts says power shortages will not hit the 2010 event.

“Four big generators will be installed that will provide enough capacity to keep the stadium going,” he says. With floodlights, sound systems, electronic access control and many other systems reliant on electricity, absence of power means simply closing down the venue. Use of generators has therefore been made compulsory by FIFA.

Malcolm Schütte of Philips Lighting South Africa says that this is understandable. “An average stadium can only switch on its lights in banks. When they are all switched on at once, demand for power is too much so a black-out could occur.” The effect could be disastrous – something for which generators could provide a solution. To be completely on the safe side, electricity from the national grid will therefore only be used as a back-up in 2010.