arc5410 Advanced Structure and Construction

3.0 Vertical Structural Systems Pt. 4

Seagram Building 1958 Brunswick Building 1966 Hancock Tower 1970 Bank of China 1989

Progression in the expression of structure from curtain wall to framed tube to 3D mega structure.

• conceptualization of the structure from a series of 2D shear resisting planes to a 3D integrated structural form• articulation of separate systems for lateral and gravity• change in expression of the skyscraper from a neutral exterior skin (curtain wall) to a primary structural frame• challenges the spatial continuity and total enclosure of the stacked, repetitive columnar supported floor plate.

Bank of the Southwest Helmut Jahn and Wm LeMessurier Houston, Texas 1982

Comparison of types of building structures based on the bending rigidity index (BRI).

See Ch.2 Tower and Office p.80

M.L.C. Center Harry Seidler / P. L. Nervi Sydney, Aus. 1978

Dharmala Headquarters Paul Rudolph Jakarta, Indonesia 1982

Atlanta Marriot Marquis Hotel John Portman Atlanta, GA ca. 1977

Petronas Towers Cesar Pelli / Thornton-Tomasetti Kuala Lumpur, Malaysia 1997

Structure of the Petronas Tower has an outer ring of 16 cylindrical r/c columns of high strength concrete (up to Grade 80). Charles Thornton, structural engineer, refers to it as a “soft tube”. In-situ concrete construction was chosen because of local practice and because of the stiffness against wind sway provided by concrete. The tower resists lateral forces with both a perimeter “tube” of columns and an inner r/c core.

Mega or Super frame concept Commerzbank Norman Foster Associates

Various forms of transfer structures in tall building design (see Jack Zunz and Chris Wise Transfer Structures)

• integration with lateral stability system. For e.g. Bank of China or Myron Goldsmith’s theoretical tower.

• reduction in number of foundation elements where soil conditions allow.

• integration with mechanical services: vertical zoning combined with multi-tier transfer structure

• reduced construction time: multi-tier systems allow simultaneous floor construction at different levels

Johnson Wax Headquarters Tower Charter Bank

PSFS Tower First Wisconsin Center

Standard Bank of Johannesburg, South Africa 1970

Example of tall building with a core tree structure: floors are suspended from cantilevered arms in groups of ten floors.

Overseas Chinese Banking Corporation Centre I. M. Pei Singapore 1976

Example of a multi-tier compression frame transfer structure.

Grovesnor Place Sydney Luk Yeung Sun Chuen Estate Hong Kong

General principles guiding the design of the HSBC.

• re-thinking / re-interpreting the program (“never as simple as it seems”)

• commitment to new materials and new technologies

• planning flexibility:

i) the service sandwich (HVAC between floor and suspended ceiling)

ii) long-span structure to enable flexible space planning

• team approach: use of new materials and methods of production required working together with specialist engineers and

manufacturers to test and develop new products (introduction of performance specifications)

• minimalist aesthetic: fewer parts to be pre-fabricated and site assembled

(kit - of - parts approach reminiscent of Charles and Ray Eames)

• rapid assembly: introduction of fast-track construction. Early construction and design development proceed simultaneously and save

money by shortening the construction time period.

• life-time building costs: “It’s not what it costs you to build it, it’s what it costs you to run it.”

Note the middle upper chord of the trusses in the photograph (not shown in the drawing at left). This upper truss chord is omitted on the exterior trusses because the floors are set back from the plane of the truss. On the interior trusses it supports floor framing.

The important “butterfly” connections at the middle of the lower chords of the trusses. The ‘butterfly’ joint contains three single pin connections each requiring a tolerance of 0.3mm. This causes the collar to fit ‘tight as a glove’ around the inserted pins.

Large X-bracing at the truss levels provide lateral stiffness to the building in the north-south direction (perpendicular to the façade).

Envelope details

Raised floor. The HSBC Building had the first raised floor used in a commercial building. The floor system was developed by Foster Associates working with special contractors in the aircraft industry. The size of the panel (1200mm x 1200mm) is determined by maintenance requirements (weight limit for two men to lift) and stiffness.

Two views of the central atrium which “replaces” the memorable main banking hall of the former bank building. Public entry to the hall (and the building) is provided by the angled escalators (feng shui inspired) that pierce the suspended glass enclosure (the former vaulted ceiling turned upside down) bringing visitors to the double height main bank floor.