Informing design
2.20 Mode shapes, first three fundamental modes of vibration, cable net facade, Poly Corporation Headquarters, Beijing (CN) 2007 2.21 Poly Corporation Headquarters 2.22 Rocker mechanism, Poly Corporation Headquarters 2.23 Pulley testing, Poly Corporation Headquarters 2.24 Detail of rocker, scale 1:50, Poly Corporation Head quarters 2.23
brated and has become the centrepiece in the atrium. The other structural innovation is the glazed eight-storey glass “lantern”, suspended from the building structure within the atrium space, which houses a museum of bronze sculptures repatriated from the international auction market. The cross-braced steel frame is suspended from the cable-net wall’s diagonal cables, while a backup steel frame allows it to cantilever from an adjacent building service core in the event of damage to the cable system. This backup frame provides a stressing support for pretension in the diagonal cable, the forces of which exceed the entire weight of the “lantern”. This combina tion allows for its unique, seemingly lightweight structure to float above the foyer floor. The effect is that of a transparent rectilinear space that seamlessly interlocks with the building. Through their exposure, the structural elements inform the building design. The synthesis of structure and form at SOM, combined with a clarity of innovation, has evolved historically from a company culture of technology and design to the makings of a structural theory. This structural theory reveals an understanding of the complexity of creating clear and direct forms, which could further expand investigations of new structural form. The fact that SOM engineers realise the signifi cance of designing even structures that are hidden, covered by layers of building materials, ensures an honesty of expression deep below the surface. Exposed rational structures express a direct structural meaning and purpose which play a double role as form.
References: [1] Rappaport, Nina: A Deeper Structural Theory. In: Architec tural Design – Special Issue: The New Structuralism. Design, Engineering and Architectural Technologies. July/ August 2010, pp. 122 –129 [2] Ibid. [3] This is described in detail in: Rappaport, Nina: Deep Decoration. In: 306090 – Decoration, Vol. 10, 2006 [4] Structural Stainless Steel Case Study 10: Schubert Band Shell; available online at http://www.steel-stainless.org/ CaseStudies
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1 151 ≈ 15.2 mm strand cable, bundled, Ø 226 mm 2 121 ≈ 15.2 mm strand cable, bundled, Ø 206 mm 3 Metal plate to receive strand anchors 4 Plate metal clevis attachment 5 Secondary steel pin 6 Upper primary steel pin 7 Lower primary steel pin 8 Web stiffener plate 2.24
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