Aerodynamic Modifications to the Shape of the Buildings: A Review of the State-of-the-Art

The development of high strength concrete, higher grade steel, new construction techniques and advanced computational technique has resulted in the emergence of a new generation of tall structures that are flexible, low in damping, slender and light in weight. These types of flexible structures are very sensitive to dynamic wind loads and adversely affect the serviceability and occupant comfort. For a typical tall building, oscillations have been observed in the alongwind and crosswind directions as well as in the torsional mode. To ensure the functional performance of tall flexible structures and to control the wind induced motion of the tall buildings, generally different design methods, various types of passive as well as active control devices and various types of aerodynamic modifications to the shape/geometry of the buildings are possible. This review paper presents an overview and a summary of past/recent work on various aerodynamic modifications to the shape of the buildings like corner cuts, chamfering of corners, rounding of corners, horizontal and vertical slots, dropping of corners, tapering etc. to reduce the wind excitation of tall flexible buildings and its application in some of the tall buildings across the world.