In yet another impressive feat of architecture, Zaha Hadid’s 44-storey skyscraper joins pieces by Arata Isozaki and Daniel Libeskind in the heart of a new development in Milan. The avant-garde 170 m tower contorts as it rises, presenting a host of engineering challenges.
Zaha Hadid-designed twisting office tower, rising above downtown Milan
The building features 39 storeys reserved for high-level executive functions, and combines this with easy connections from the galleria to the city and the local metro station below via a shopping area within a bifurcated covered walkway at the foot of the building. The twisted, algorithmically controlled building enables users to enjoy spectacular views from the most opportune place on each storey, but required a carefully considered design.
The irregular form was achieved by staggering each floor plate slightly, and modelling was crucial to gather information about the behaviour of the proposed building. Our advanced geometry team developed their own software to gain an understanding of the forces created, and could then use this to experiment with dimensional and structural changes while we were deciding on materials and layout.
Despite its complex appearance, we opted for a conventional central core to provide lateral stability and kept the structure as simple as possible. We were unable to utilise straight, central columns since their relationship to the core would change at each level, so instead we proposed high-strength steel perimeter columns, tapering through the building, with carefully designed curves which would simultaneously provide support and a template for the glazed façade.
Again, the torsion applied by the building’s shape required us to investigate the properties of these large panels of glass in detail. Six types of panel were utilised in a double-skin; warm- and hot-bent glass were specified in areas of extreme warp. The inner skin and the concrete floors are sealed at each level, allowing flexibility in the cavity and the position of the outer skin.
2019 ACI ‘Excellence in Concrete Construction Award
2019 The Plan Award