The Abdul Latif Jameel Corporate Headquarters building in Jeddah was envisaged as an open-plan, social office that is expected to house 2 300 staff.
According to architect Andrew Bromberg of Aedas, the client’s vision was for the facility to provide various social interaction zones through a bright, open, and flexible layout. Such designs are uncommon in Saudi Arabia, where intense heat means that building designs are dictated by the need for thermal comfort, rather than space or brightness.
To create the bright, open spaces in this challenging environment, Aedas oriented the L-shaped building so that the solid face of the building faces west, thus bearing the brunt of the intense afternoon sun, which can hit above 40 degrees Celsius.
The building’s unique tapered L-shaped structure meant that Aurecon’s structural engineers had to devise a tailored support structure that would not compromise the design vision of an open-plan space.
According to Andy Mak, Principal Structural Engineer at Aurecon, the L-shaped office areas are arranged in a manner which gives the architectural tapering effect - both legs of the L-shape are arranged slightly differently from the adjacent floors. This created an intriguing challenge in determining the column layout to suit the open plan office and also integrating it with the car park layout in the basement.
Aurecon’s engineers developed sophisticated models using Revit design software and worked to integrate that with Aedas’ models produced using the Rhino platform.
The teams went through many iterations of overlaying the Revit model and the Rhino model to coordinate the optimum column arrangement. In the end, they decided on inclined and kinked columns on one leg of the L shape. This worked very well with the interior architecture and also avoided major transfer beams in the floors.
The link bridges were an integral part of the design and the key visual element in the atrium space.
For architecture, the bridges are a key visual element in the atrium space. But they also provided the only route to get building services into the office space.
Structurally, the link bridges were used to anchor the L-shaped floors back into the large lift shafts, meaning that horizontal forces induced by the kinked columns and all of the seismic storey shear forces had to be channelled through the four link bridges on each floor.
Mak also noted that the strength and stiffness of the structure was provided by the use of high-strength reinforced concrete. However, for the building’s office floors, post-tensioned concrete was used, as it could better withstand the tension from the tapered columns, building a stronger connection between office floors and elevator shafts.
Another significant challenge encountered by Aurecon engineers during the building process was the absence of solid bedrock beneath the site.
Unusually for Jeddah, where bedrock is usually found at relatively shallow depths, the building sits on top of dense sand where the bedrock is more than 60 m below ground. The site is located at a dip in the bedrock where the Hijaz Mountains meet the Red Sea, and this site condition meant that long friction piles were required to support the loads of the building.
To minimise the loads onto the piles, soil structure interaction analysis was conducted, incorporating the piles and soil into the structural analysis model. This facilitated the design of a piled raft foundation system where 20 per cent of the foundation load was shed from the piles into the ground bearing raft, delivering a more efficient design, explained Andy.