Aerodynamic Effects of Height-to-Width Aspect Ratio Variation in Tall Buildings-Numerical Study

High winds are considered among the most dangerous natural hazards besides earthquakes to tall buildings. Under high wind, tall buildings experience aerodynamic effects that play a crucial role in determining their principal wind induced responses. Nowadays, high-rise buildings are often remarkably flexible, low in damping, and light in weight. Thus, they generally exhibit increased susceptibility to wind-induced responses. Consequently, it has become necessary to develop tools to enable structural engineers to determine wind effects on tall buildings with high confidence from structural integrity and serviceability perspectives. In this regard, computational fluid dynamics (CFD) simulation is a suitable option for studying the sensitivity of wind pressure on tall buildings. The numerical study presented in this paper addresses the aerodynamic response of a standard tall building through large eddy simulation (LES) employing the consistent discrete random flow generation technique (CDRFG). Applying the CDRFG technique to generate the inflow boundary conditions allowed an accurate depiction of the turbulence spectra. The aerodynamics behavior has been investigated for four same-height (180 m) tall buildings with different height-to-width ratios (i.e., 6.0, 4.0, 3.6, and 3.0). Based on the outcomes of the numerical study presented in this paper, it has been found that the wind-induced responses obtained from the LES models led to an acceptable estimation of the wind pressure distribution and reactions of the buildings studied in a time-efficient manner.