Entertainment in Dubai is entering outer space with the city's latest theme park.
Who as a child didn't imagine shooting off into space? Looking out of a spaceship window at the other planets in the galaxy is a dream made in movies. And that vision is now being translated into reality in Dubai.
Over the past year, five giant, coloured domes have been taking shape in Zabeel Park. These form the heart of Stargate, a mixed-use entertainment complex based on the concept of a crashed spaceship, complete with its own resident aliens Ajeeb and Ghareeb. The domes represent the spaceship and four planets - earth, Mars, Saturn and the moon - and on completion will be filled with different activities. But this is only the tip of the project. The bulk of the 24,000m2 complex has been constructed below ground, creating unique challenges for the construction team, with co-ordination and adaptability being essential to the project's completion.
Dubai-based Osus is undertaking the project on a build, operate, transfer (BOT) basis on behalf of, and in partnership with, Stargate owner Dubai Municipality. Sensaire Services won the contract for the shell and core MEP services in competitive tender in May 2006 and immediately began work onsite.
This is one of the rare jobs in Dubai that does not use district cooling; it's a self-contained unit.
"This job is basically an underground entertainment park," explains Alan Hart, Sensaire Services' contracts manager. "It's broken up into five zones, each with a different theme." The area below ground is spread over two storeys and formed in a circle, with each of the above-ground domes sitting atop one of the zones and defining an area. Five tunnels divide the zones and lead from an outer ring to a central meeting area. Activities that are set to be installed include an ice rink, go-kart track, roller coaster and theatre, in addition to retail areas and electronic games arcades.
Space age services
The shape and layout of the project made installation of the MEP services complex. Tight plant spaces and the continuous development of the fit-out design has added to the challenges.
The first step Sensaire took to tackle the project was to break the work down by area, with different teams undertaking the installation in each. "We tried to treat [the project] like two different jobs, with the underground area and the domes as separate parts," explains Sensaire Services project manager Lionel Bean. The main installation in the domes was carried out first in order to maintain the overall project programme.
The domes comprise of a double-layer glass-reinforced plastics (grp) skin that are separated by an air gap of around 600mm. The MEP services have been installed within this gap. "The outside skin was put on [the structural frame] first; we then put in our services, and once they were complete [the main contractor] could install the second skin," explains Bean. "Until we'd finished our services installation they couldn't put the second skin on, so it was a top priority to get our services in the domes, then the contractor could start doing its fit-out," he added.
Installation in the underground building was again prioritised according to task and area. The main chilled water pipework was the first to be installed, followed by the main air conditioning ductwork. "This is one of the rare jobs now in Dubai that does not have district cooling," states Hart. "Because it's in Zabeel Park there isn't any facility available. Instead it's a self-contained unit with its own chillers and cooling towers," he explains. Two 975TR chillers provide chilled water to VTS Clima air handling units located in individual plantrooms on the development's mezzanine level that provide cooling across the project.
The main chiller plant and electrical rooms are sited externally adjacent to the development, with services distributed underground to the edge of the circular site. Two mains chilled water feeds serve the development; on entering the building these are routed at ceiling level around the outside diameter, with branches feeding from this into individual plantrooms for each zone.
The distribution of electrical services follows this pattern also, with mains brought in through a central corridor then distributed via a major traywork circuit. Within the domes, two main risers feed directly up from the plantrooms in the underground building, the ductwork and cable trays then feeding upwards between the dome skins.
A similar amount of power and air conditioning is supplied to each zone, varying proportionally according to the different volumes to be served within the domes, which range in size from 180-220m2. The dome that will contain the ice rink is the exception, with an independent, dedicated chiller system installed to provide the additional cooling required.
A central building management system (bms) ensures the independent control of each of the zones. "If there was a fire, all of the services would be controlled to cope with the fire in [the zone it's in] rather than it affect the other areas also," explains Bean. The sprinkler system is zoned according to the five sections of the building, with further zoning within these areas, enabling the system to be activated in the area where it is immediately required without the entire building being affected. "All air conditioning ductwork is fire-rated because it's used for smoke extract as well," adds Hart. "If a fire did occur, the supply will spin into extract so we can exhaust all the fumes."
To distribute the services around the edge of the circular building and through the domed shape of the planets, the individual sections of pipes, ductwork and cable tray were prepared in situ then joined together. Special materials were also used to ease the process in certain areas, for example the phenolic foam-based ductwork PAL has been installed rather than a metal alternative. "It's easier to cut on site to fit the shapes needed. It costs about the same as galvanised steel, but you can turn a job around much quicker," explains Hart. "It's lightweight, quicker to install and [using it] takes out the factory time. If I want a piece of ductwork made that is a funny shape it may take two to three weeks [to have it manufactured offsite in metal], but if I have it made it out of the phenolic product it can be made in three hours, then the job is done," he stresses.
One of the biggest challenges that Sensaire has faced on the project is the changing content of the complex and the subsequent effect on the MEP services loads. Continuing advances in technology and the fast-moving nature of the entertainment sector have meant that the specific contents of each zone have been developing throughout the project programme. "The project is dynamic and as it's an entertainment park, certain things are changing all the time," explains Hart.
This has added to the task of the MEP contractor as the amount of cooling and electrical capacity needed has risen as a result. The project development has meant that the size of certain mechanical plant, cabling and ductwork have increased from the original design, with adaptations needed to the installation to accommodate these changes. Coping with the developments has entailed close co-ordination with both the main contractor and other subcontractors on the project.
"The engineers have co-ordination meetings nearly every day," explains Bean. "The main contractor ECC has its own MEP division which is carrying out the overall co-ordination and they hold meetings twice a week. We also have site walkabouts three times a week where the engineers and foremen physically check what has been done on site," he explains.
As the MEP services in the underground building are concealed, Sensaire is working very closely with the ceiling and structural contractors to ensure that the project can be completed as efficiently as possible. The main cable routes, for example, pass through two of the tunnels, so ceilings in these areas have been left open until the final cable sizes are determined and these can be installed. The other three tunnels, meanwhile, have been completed.
"Mechanically we're about 85% complete; electrically we're down as low as 25-30% because the cable pulling hasn't started yet," explains Bean. The final electrical loads are currently being confirmed, however the cable trays have been installed, so following DEWA approval, the firm has simply to pull the cables through the building's distribution system.
"We're trying to complete the whole of the installation, so that it's physically ready apart from the power connection," explains Hart. "We've got around 48 cables of 11kV ready to run into the building, which we can't do at the moment," explains Hart, "the logistics have been planned so that our installation will impact the job [as little as possible]."
The fitout of the project's domes is now well underway and plans are already on the drawing board for the future retrofit of a large-scale theatre in one of the underground zones. Once open, Stargate is sure to make a few dreams come true.