Dubai’s preoccupation with high rise buildings is notorious, but change is underway at the under-construction Downtown Dubai complex.
More from: Middle East | Market report 2016
Here, between the famous Burj Khalifa, the Address skyscraper and the Dubai Mall, the city’s first purpose built multi-format theatre is nearing completion.
Situated on a plot area measuring around 195m by 145m, Dubai Opera is uncharacteristically low rise. The structure and redevelopment of the surrounding plaza is designed to fit with the ruler of Dubai’s vision for the area as a cultural hub.
“The project is in line with Sheikh Mohammed’s vision for Dubai as a cultural destination,” says Atkins architect Janus Rostock, who is part of the project team.
dubai opera aerial
“Previously, the boulevard was a nice environment but nobody was really using it. There were too many blank façades, and very little human interaction. Many of the older buildings in Dubai often have little detailing in the façade, but this is changing.”
As part of the project, Atkins has proposed a new masterplan for the complex which involves pedestrianising the area by introducing more underground car parking and improving outdoor facilities and kiosks with active frontage on retail plots. “It was a very introverted site,” states Rostock. “But we are creating an extroverted boulevard for people. It has gone from being an area designed for cars, to being an area for people.”
We are creating an extroverted boulevard for people. It has gone from being an area designed for cars, to being an area for people
At the heart of the city’s new cultural quarter, Dubai Opera has been designed to be more “extrovert” than many of the neighbouring buildings.
“The challenge of building in a high rise environment is ‘how do you make the building stand out?’” says Rostock. Much like the Sydney Opera House, Dubai Opera is set to be an iconic addition to the city’s skyline.
The building is designed to glow like a lantern at night, so the concave, internal timber structure had to be evenly lit. The theatre lighting was designed with three different lighting systems which include 1,500 channels for dimming and lighting control. Rostock explains that there will be no façade lighting for the building as the intention was to “create a lantern” rather than a lit object, emphasising the “seamlessness between the public realm and the lobby space”.
The auditorium is enclosed in a 400mm curved concrete wall to give the required architectural shape and meet the stringent acoustic requirements. The roof span is 34m, formed of a steel truss and deep concrete beams above the stage which span between internal reinforced concrete walls. All of the main slabs, shear walls for lateral stability, and external raking columns up to the upper balcony level are concrete. The outer columns at the upper balcony level are steel to support the steel roof.
The roof span is carried by 4.2m deep steel trusses, with an average spacing of 3.5m fixed into a 500mm thick section reinforced concrete wall at the edges. The cantilever triangular trusses of the balconies are fixed into the reinforced concrete shear walls, which acts as supporting back span.
The overall design process for the project took approximately 14 months to complete and construction began in April 2013 with the start of piling. Ground conditions on site have been challenging, with weak to very weak rock of calcarenite and sandstone and a minimum bearing capacity of 550kN/m2 at the foundation level. The groundwater table ranges between -1.45m to -1.75m DMD (Dubai Municipality Datum), but the design groundwater table is considered at 0.00 DMD to allow for tidal and seasonal variation. The foundation is a 1.2m thick raft supported by 244 tension piles, which measure 1.5m in diameter and 14m in length. The tension piles have been used to stabilise the building against buoyancy and reduce the raft’s hogging moment due to uplift of high groundwater table.
The challenge of building in a high rise environment is ‘how do you make the building stand out?
Typical basement wall thickness is 600mm, reduced to 500mm above basement two level. Typical basement slabs are cast insitu with 300mm thickness and average spans of 8.5m by 8.5m, while the ground slab for the plaza area was designed to support 1.6m of landscape fill above it. It is 350mm thick with drop panels at the column locations to reduce the need for extra slab reinforcement.
The basement is four stories below road level with an excavation level of -12.15m DMD. A combination of deep shoring with ground anchor techniques and open excavation was used to support the excavation sides depending on the plot boundary conditions. Close proximity to existing structures, meant that stringent monitoring measures had to be undertaken to check stability of the adjacent building foundations. Secant pile is used at the side adjacent to the existing boulevard underground car park, while diaphragm wall with two levels of ground anchors have been used at the edge adjacent to the existing Standpoint residential towers to control and minimise lateral movement in the soil. Open excavation techniques have been used at the other boundaries wherever applicable.
Despite the challenging ground conditions and close proximity to existing buildings, Atkins has relished the challenge of delivering the centrepiece for Dubai’s new cultural hub. Rostock says more than 160 Atkins staff have so far been involved over the course of the project.
“Designing and constructing an opera house is very much a symphony – you need everyone to play the same tune,” he says. Following completion of the main construction phase in August 2016, the real performance will commence with tickets already on sale for inaugural performances at the theatre later this year.