Hong Kong's tallest tower rising in Kowloon

The 484 m, 118-story International Commerce Center (ICC) will be the tallest building in Hong Kong and the third tallest in the world when construction is completed in 2010. The structure however sits atop a major fault zone and is surrounded by several sensitive structures and facilities. With these challenges, the design team selected a friction pile foundation consisting of 242 barrettes that extend to an average depth of 80 m. The team adopted a circular cofferdam 76 m in diameter as the permanent retaining structure for the basement and pile cap construction because the hoop stiffness of the cofferdam would help to minimize the movement of the adjacent structures, ground, and utilities during construction. The project is using grade 90 concrete with high modulus of elasticity and with volcanic aggregate added to improve stiffness.