Cutting edge 3D modelling techniques are proving invaluable in the development of Abu Dhabi’s International Midfield Airport terminal.
Commissioned by the Abu Dhabi government, the $2.94bn terminal will cover an area of 630,000m2 and service up to 20 million passengers per year.
Designed by architecture firm Kohn Pedersen Fox (KPF) the structure is cross-shaped with undulating roof canopies and cavernous internal concourses. It is located between two parallel runways.
Engineers from RMD Kwikform have been using the software for the complex design and geometry of key parts of the structure.
A major design challenge was the formation of the main terminal building with its curved roof structure. This required the installation of some of the world’s largest steel archways and girders.
Curving in both the horizontal and vertical axes, the construction of the terminal building relies on millimetre accuracy to install each fabricated segment, which forms the arches and a central girder.
The engineers worked with steel roof sub-contractor, China State Construction Engg Corporation to design components using 3D modelling for the phased erection of the arches. This process included the design of a heavy-duty support system for the erection of the steel arches.
With a need to support the arches in both the vertical and horizontal planes, a critical component of the solution was the design of a special ball joint, with an additional jacking frame system.
In order to ensure the frame was able to cope with the key loading forces and changeable climatic conditions, including high wind and heat, the engineering teams used the latest modelling technology before components were then fabricated and tested.
RMD Kwikform UAE general manager, Chris Jardine, said: “Loading and stresses on the formwork and shoring were different for every single node point; we had to take a 3D model to form a solution that could operate safely and securely. As the contractor wanted to be able to use the frames multiple times, our solution had to be flexible enough to cope with the adjustments required at different parts of the erection phasing.”
The engineers had to vary the footprint of the towers, to share the load, and cope with thermal movements caused by temperature variance from day to night. The support system had to cope with vertical loads of up to 500kN and horizontal loads of up to 75kN.
Finally, with each of the 16 steel buttresses and concrete slabs mounted two floors up, the team had to design a back propping solution for the two levels below the raft.