Aerodynamic optimization of super-tall buildings and its effectiveness assessment

To improve safety and serviceability of super-tall buildings in strong winds, aerodynamic optimization of building shapes is considered to be the most efficient approach. Aerodynamic optimization is aimed at solving the problem from the source in contrast to structural optimization which is aimed at increasing the structural resistance against winds. However, there are two challenges that usually limit the applicability of aerodynamic optimization in design practice. One is a potential conflict between optimization schemes and other design aspects, and another is a potential conflict between cost and effectiveness. To minimize these conflicts, it is important to conduct aerodynamic studies in early design stage to gain reasonable assessment on various optimization options. This paper summarizes the aerodynamic approaches that have been used with success in building designs, and discusses the principles and effectiveness of these approaches. To provide a guideline for preliminary design, this paper proposes a practical approach to assess the effectiveness of tapering, twisting and stepping, the three common schemes of aerodynamic optimization in super-tall building design.