Effects of geometry on the wind response of super-tall towers

Effects of geometry on the wind response of super-tall towers Conference

Irwin, P. (2008). Effects of geometry on the wind response of super-tall towers . 314 10.1061/41016(314)86

Tall buildings become increasingly sensitive to wind as they go higher and for super-tall towers, which are going up at an increasing rate, wind becomes the dominant factor in the structural design, not only for strength but also for keeping the building motions within a comfort range for the occupants. Along wind forces are important but even more important are the crosswind forces. While stiffening the structure, increasing its mass, or adding supplementary damping systems are all ways of reducing the response, it must be remembered that the source of the wind excitation is interaction of the wind with the building's shape. The dominant form of excitation of building motions is often vortex shedding. Various shaping strategies such as tapering, varying the cross-section with height, softening the corners, using spoilers, and inserting openings in the building have been used to mitigate or even completely suppress vortex excitation. The alignment of the tower with strong wind directions or even with other towers nearby can also be important. Substantial cost savings are possible if the effect of shape is taken into account early in the design. © 2008 ASCE.