Architect and Builder April 2017 | Page 64

THIS SPREAD : The second building accommodates the visitor ’ s reception area and the executive functions and is the eccentric one ; organic , innovative and generous
Architectural and Engineering Innovation The first building ’ s innovation is clearly in its defiance of gravity ; all of it , but for the triple volume entrance foyer , hovers above the ground , from which it is scantily propped . The 30m-long office wing is supported by only two large concrete columns , and by steel pins on the blade wall beyond , from which a 6m-long executive office also cantilevers . This feat is made possible by a highly engineered , threedimensional ‘ Vierendeel ’ truss system that frames the wing on all of its six façades .
The second building is equally innovative in its defiance of gravity , as it hovers over the water of the dam . In order to keep the sub aqua columns as visibly slender as possible , a series of smaller columns that carry the building above with a network of integrated transfer beams , connect underwater to form mass concrete piers .
The ‘ skin ’ on the second building was an intricate collaboration between the architects and engineers and required a secondary steel sub-structure , that was digitally modelled , and which was used to profile the steel members . This process resulted
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