Torsional moments of tall buildings

Tall building asymmetries in planform shape, structure and mass distribution can all contribute to the generation of large wind excited moments about a vertical axis and also large displacements and accelerations. This torsional response can be further complicated by interference effects from nearby buildings and modes which combine rotation with sway displacement. This paper will describe the experimental technique used in model studies in the boundary layer wind tunnel at Monash University to determine torsional moments and displacements, and will show that mean torsional moment coefficient can be generalised as a function of building planform aspect ratio squared.