Structural Design of Shanghai Tower for Wind Loads

Abstract

Nearby Jin Mao tower and the World Financial Center, the 632-meter, 121-story mixed-use Shanghai tower will be the tallest super tall tower in the new Lujiazui Finance and Trade Zone of Shanghai. Due to the super tall height, curved façade and spiraling form of the Shanghai tower project, wind is the dominant lateral load and governed many aspects of the structural design. To precisely determine the design wind loads, a detailed wind climate study was conducted. The influences of typhoon events and typhoon profiles were considered in the wind climate study. Due to its long structural period, the across-wind load of the Shanghai tower project is prominent. Aerodynamic optimization studies were conducted to reduce the correlation of vortex shedding along the building height, and thus reduce the across-wind building response. The optimization results show that the across wind load can be effectively reduced with certain building configuration. Detailed wind tunnel studies, including HFFB and HFPI studies, high Reynolds number tests and aeroelastic model tests, were conducted to accurately capture the wind load on the building. The wind load parameters, such as the Shape factor, Strouhal number and the terrain type, were obtained and derived from the wind tunnel studies. The wind load and wind induced structural responses obtained from the wind tunnel studies were then compared with those calculated based on Chinese load code. The design criteria for the ultimate limit check and serviceability limit check of Shanghai tower for wind loads were discussed. Finally, the building vibration under wind load and the related human comfort problem is addressed. Different human comfort criteria are compared and the building acceleration results from both the wind tunnel tests and code-based calculation are discussed.