Jean Nouvel’s Louvre Abu Dhabi Museum
The museum’s 183m domed roof has taken months of workshops and modelling to achieve its floating structure and intricate perforated pattern
Architect Ateliers Jean Nouvel
Design engineerBuro Happold
LocationSaadiyat Island, UAE
Jean Nouvel has described the roof to his Louvre Abu Dhabi Museum as being like a “parasol flooded with a rain of lights”.
Hala Wardé, a partner at the French architect’s practice, says Nouvel wanted “something very horizontal and low that played with shadow. The rain of light is an effect you find in an Arab souk or forest and Jean wanted to recreate that emotion when you move from being under a very harsh bright sun to being under an umbrella”.
This intricate effect is what the design team has achieved in the final design of the 183m-diameter “floating” domed roof. It has taken eight months of workshops and physical and computer modelling as well as a great deal of trial and error and a dose of intuition to reach the stage where the roof structure isn’t visible.
Tim Page, an associate director at Buro Happold, recalls: “It was a very big moment when we achieved the dematerialisation of the roof structure and managed to remove the rectilinear truss.”
The €500 million project began on site in October 2007, after Nouvel won the competition to design the scheme. Its spherical dome shape was determined early on and is a direct reference to Arab culture — the roof’s pattern is also based on traditional motifs. The 24,200sq m collection of cubic and rectangular exhibition buildings contained under the dome will be sited in the tidal fringes of Saadiyat Island, a 27sq km natural island in the archipelago stretching eastward along the Arabian Gulf coast from Abu Dhabi.
The Louvre Abu Dhabi, which will display exhibits from the Louvre in Paris, is one of four buildings planned for the island’s Cultural District, which will be linked to the mainland by two new bridges.
Modelling the dome
The design team wanted to create a cool, welcoming environment in Abu Dhabi’s harsh desert climate. Its key way of achieving this was through the roof’s unique fractal perforated pattern.
The full perimeter of the dome is open at ground level, with a 14m gap from ground level to the edge of the roof’s lip. The roof rises to a maximum height of 37m at the centre from ground level.
Smart Form, a bespoke computer modelling programme developed by Buro Happold’s Smart Solutions team, was used to design a structural form that optimised the roof’s structural efficiency.
What has evolved is a dome with an outer layer of cladding composed of five layers of unpainted stainless steel and aluminium pierced with apertures of varying shapes and sizes. There will then be a 5.5m gap incorporating a steel tubular truss — the steel members will be of 10 varying sizes — which will support the cladding.
The inner layer of cladding, also composed of five layers of pierced stainless steel and aluminium, will be bolted and welded underneath the tubular truss. The cladding panels span rigidly as extruded metal sections without filler or insulation between supports mounted on the top and under-side of the structural truss.
The 5,000 tonne dome will be supported by four 5m x 5m reinforced concrete piers — each one will have a single bearing designed to accommodate thermal and deflection movements. The piers will not be solid and some will provide an access stairwell to the roof. The supporting piers will be concealed within the museum buildings to give the impression the dome is floating above them.
A number of physical models of the dome were created, but none were quite as large as the 20m x 20m replica of a section of the roof which has been built close to the site and used to verify the roof pattern and complex light paths. This huge model has enabled the design team to assess the effects of different layers of cladding and track the shafts of light as the sun moves.
Smart Solutions’ integrated modelling and optimisation
Author Shrikant SharmaSmart Solutions, Buro Happold’s computational modelling team pushed the boundaries of integrated modelling and optimisation in their work on the Louvre Abu Dhabi dome.The project required innovation on two levels. Firstly, the use of modelling and analysis tools to enable the geometry, layered arrangement and sizing of the cladding pattern and the structural members to interact with each other to deliver the desired aesthetic, structural and environmental performance.Secondly, the combination of these tools so that they work across the concept design to the final detailing within an integrated modelling environment, facilitating a smooth and efficient integration of architectural, structural engineering, facades and environmental design parameters.The project used the team’s in-house tools Smart Form — a geometric mapping and optimisation tool, and Smart Sizer — which optimises the size of the structural members. The two work in tandem and use a combination of approaches involving dynamic relaxation, geometric mapping, genetic algorithms, topology optimisation and virtual work based evolutionary optimisation. These integrate with commercial cad and structural analysis packages to cover the macro (optimum form) to micro (multi-dimensional structural grid layout and member sizes), enabling a design where every member is optimised for deflection, stress and buckling criteria.The tools were implemented within a Digital Projects software package so that the resulting 3D model was fully parametric, integrated, and shared by the design teams. This enabled simultaneous modelling of the concept and detailed design elements.The integrated modelling has led to efficiency and cost savings. Behind the complexity of the fractal-like roof pattern lie simple concepts, rules and standardisations. Each of the cladding layers, including the structure, is based on a simple base pattern combined to create the final effect. Each single member of the structure and the cladding layer is chosen from a handful of standard element sizes.Shrikant Sharma is an associate of Buro Happold and heads Smart Solutions.