Histar®: best solution for Shanghai World Financial Center's innovative structure

ArcelorMittal's Histar® steels form part of the Shanghai World Financial Center's structure, providing the necessary strength with reduced section sizes and weight. It contributes to the innovative structural concept that won the CTBUH Award for Best Tall Building Overall and Asia & Australasia in 2008. The 101-storey and 492 m landmark tower, a symbol of commerce, culture and the city's emergence as a world capital, was the world's second tallest building when it opened in 2008.

Detailed information

Located in Shanghai’s Pudong district, a special enclave designated in the early 1990ies as the city’s business centre, the SWFC is a mixed-use building conceived as a  truly vertical city: a foyer with shopping malls and restaurants in the lower part, offices and conference facilities and a hotel between the floors 79th and 93rd and the world's highest observation deck at a height of 474 metres (in 2008).

Its simple yet contemporary design creates a stunning effect. It combines two intersecting arcs and a square prism, forms that represent the ancient Chinese symbols for earth and sky. Its shape contributes to the building's efficiency as the wider base for the lower floors accomodate offices and the straight lines of the smaller upper floors where the hotel rooms are located.

Histar® steel grade chosen for innovative structural concept & effective use of material

The supporting structure of the skyscraper consists of a central reinforced concrete core and a massive framework of steel columns and girders. The design employs an effective use of material, because it decreases the thickness of the outer core shear walls and the weight of the structural steel in the perimeter walls.

Histar® high strength steels have been considered the best solution to optimize structural design by the design team architect and engineering. Thanks to the innovative in-line heat treatment QST (Quenching and Self-Tempering), the Histar® steels offer improved guaranteed values for yield strength. It was therefore possible to use smaller sections sizes with the same performance, resulting in a savings of steel used for the skyscraper's structure. ArcelorMittal supplied 10.000 tn of high-strength steels Histar® (ASTM A913-Grade 50) for the building's steel frame, in the form of W 14”×16” jumbo sections, accompanied by technical support to designer and contractor.

The façade of the building, its structure and its mechanical systems are seamlessly integrated and arranged in modules that are repeated every 13 floors, which has greatly facilitated the manufacture and installation of the relevant components and thus cut construction times, wastage of materials and structural inefficiencies. Its most distinctive feature is the roughly 50-metre wide aperture created in the topmost floors which helps reduce the stresses of wind pressure acting on the building at its summit.

The SWFC’s sustainability objectives focussed on reducing the energy expended in the construction of the building by maximising efficiency, minimising the materials and rationalising the building's geometry. Histar® contributes to those objectives, thanks to optimization of the weight of the structure and efficient use of steel material.

Architecture & safety

The relationship between earth and sky that the skyscraper evokes includes a special study of the materials used, which pursues the idea of the contrast, even if a harmonious one, between the elements. The base of the tower, clad in rough granite to a height of 24 metres, reinforces the sense of stability and anchors the tower to the ground. By contrast, the main body of the tower is clad in a glazed curtain wall that reflects the sky and gives the building a sense of lightness. The architects Kohn Pederson Fox used glazing units with a special high-performance coating designed to meet the very highest aesthetic, ergonomic and environmental standards.

The safety of the building was a factor taken into account right from the very earliest stages of design. About every 12 floors there is an escape floor in which users of the building can take shelter in case of necessity.

As regards to fire safety, the exits and fire and smoke propagation were studied using a service approach (which guaranteed a level of safety in excess of legal requirements), with computer simulations that led to some modifications in design (width of stairs, location of exits) to improve building evacuation times.

The Shanghai World Financial Center uses the appropriate design features for a mixed steel-and-concrete structure to ensure optimal fire protection and impact resistance for the entire steel structure.

Project Information

  • Shanghai
  • China
  • Architect:
    KPF - Kohn Pedersen Fox
  • 2008
  • Client:
    Shanghai World Financial Center Co. - Mori Building Co., Ltd.
  • Engineering Firm:
    LERA - Leslie E. Robertson & Associates
  • Contractor:
    China State Construction Engineering Corporation
    Shanghai Construction Group
  • Photographer:
    ©Mori Building Co. Ltd.