Award for waterfront ‘Grain Silo’ design
30 October 2018 | Web Article Number: ME201812415
ARUP was commended for their entry of the V&A Grain Silo Complex facade in the Architectural Category at the 2018 South African Steel Awards recently.
The company, an independent firm of designers, planners, engineers, consultants and technical specialists, works across every aspect of the built environment, and has been recognised for its steel projects at previous Steel Awards.
This year, the company had three project entries shortlisted for the finals – the other entries were the lobby of PwC Tower in Midrand, Gauteng in the commercial category and the Ashgate facility in KwaZulu-Natal in the factory and warehouses category.
A spectacular example of architectural adaptive reuse, the V&A Grain Silo, once an agricultural silo for grain storage, has quickly become one of Cape Town’s most desirable developments. The industrial heritage complex is now the jewel in the crown of the Silo District development, and the refurbished silo is occupied by The Zeitz Museum of Contemporary Art Africa (MOCAA) and The Silo Hotel.
The most noticeable and significant aspect of the use of steelwork on the project are the 98 pillow windows on the building. These are installed into the existing concrete frame, where existing masonry infill could be removed, at the rooms and restaurant of The Silo Hotel and on the top floor of the Zeitz MOCAA. Other significant use of steelwork in the façade packages include:
• Zig-zag windows: folded glass windows built into the silo walls at the museum ground floor, supported by steel flat plate structure).
• Trafficable skylights: nine trafficable glass panels supported by steel structure to the top of the silos over the museum atrium.
• Skylight: glass skylight between the silo building and elevator building supported by steel structure. Tessa Brunette, senior façade designer at Arup, said Arup’s brief from Heatherwick Studio was to give new life to the redundant industrial building, repurposing it into something new for the V&A Waterfront.
“Arup developed the concept of the pillowed windows following the studio’s suggestion of installing convex windows into the upper storeys of the building in order to transform it into a glowing beacon within the city bowl. Achieving the pillow window geometry was the most significant challenge.
“Working collaboratively with Heatherwick Studio, we created a parametric 3D model that established a series of geometrical and technical ‘rules’, within which the studio had full control of the geometrical resolution by defining the projection of each node and the main joint lines. This allowed the architects to drive the aesthetic resolution within an entirely technically feasible framework, and for the complex design to be achieved efficiently and act as a sound basis for procurement.”
This parametric model was used to generate a 3D model of each of the five window frames, that included the required member size and orientation that was provided to Mazor, the steelwork fabricator, to produce their steelwork shop drawings. A close working relationship was required with the main contractor, WBHO, and the specialist façade contractor, Mazor, to fabricate and install these complex and unique façade modules.
Closer to home, the Ashagate development includes three separate warehouse structures within the Umbogwintwini Industrial Complex in Kwa-Zulu Natal on a brown field site. The structures were required for storage and distribution of chemicals. The project contained 600 780 tones of steel.
Warehouse A is designed to store the flammable bulk chemicals in the facility and uses precast columns and tilt-up walls to the underside of the steel roof sheeting. The connection of the steelwork to the precast concrete elements required some unusual connection solutions for the purlins, which are chemically anchored to the top of the wall.
The steel roof is non-continuous over the whole warehouse and is designed per compartment within the warehouse for safety. In the case of fire, it will help to prevent the spread of the fire or fumes or progressive collapse and to will limit the damage done in case of an explosion or fire.
Warehouses B and C have internal racking to store mainly non-flammable liquid chemicals in containers. Arup engineers had to ensure minimal horizonal deflection of the structure in one of the warehouses due to 13m high racking being placed next to the walls and the use of Very Narrow Aisle (VNAs) forklifts for the placing and removal of the containers. The two warehouses are connected by a steel canopy spanning over the road and loading area.