The Bank of China Tower stands 70 stories tall, reaching a height of 1,209 feet. At the time of its opening in May 1990, it was the tallest building in Asia and still remains one of the tallest in Hong Kong. The famous architect I M Pei was commissioned to design the tower, a commission that required a tall unique headquarters in a typhoon-prone region that would represent the aspirations of the Chinese people yet also symbolize good will toward the British Colony.
The solution assimilates architecture and engineering simultaneously, involving an asymmetrical tower that informs both skyline and street. Comprised of four vertical shafts, the tower emerges from a 52-meter cube and reduces its mass, quadrant by quadrant, until a single triangular prism resides. The faceted prism is clad in reflective glass that mirrors the changing sky, anchoring the expansive business district and providing a characteristic vertical axis to Hong Kong’s towering skyline. The four shafts that form the building produce a modern composite structural system that not only resists high-velocity winds, but also eliminates the need for many internal vertical supports. As a result, the Bank of China uses less steel than typical for a building its size. A key issue for I.M. Pei was the symbolism of the structure for the Chinese people and the British Colony. Original plans included an x-shaped cross-brace. However, in China the “X” shape is seen as a symbol of death. As an alternative, Pei chose to use less menacing diamond forms.
The bamboo plant was also a significant inspiration for this unique building. The trunk of this massive structure is representative of the growth patterns of bamboo, the symbol of hope and revitalization in the Chinese culture. Its triangular structure of glass and aluminum evokes shoots of bamboo leaves, which represent prosperity in China and the sustenance of life.
The whole structure is supported by five steel columns, four in the corners of the building and one in the center, which together bear the weight and forces. The towers are lifted to different heights and the loads of the central column are directed to those found in the corners, forming a triangular frame. This allows the architect to design a lighter structure, because the diagonal elements required are less important, while the three-dimensional internal structure provides a clear floor that allows for future changes in the disposition of their use, thus saving energy and resources.
