Investigation of torsional aeroelastic effects on high-rise buildings using forced vibration wind tunnel tests

In this study, the torsional aeroelastic effects are investigated for high-rise buildings by carrying out a series of forced vibration wind tunnel tests. In these tests nine building models with different side ratios and structural eccentricities are considered, where the structural responses and surface pressures for each model are measured. The method used to determine the torsional aerodynamic stiffness and damping ratios from the experimental data is introduced. The effects of the vibration amplitude, side ratio, and structural eccentricities on these two ratios are examined. The results show that the amplitude of the vibration does not have a significant effect on the torsional aeroelastic effect. Also, the torsional aerodynamic stiffness ratio can be neglected in the absence of structural eccentricity. However, the side ratio has a significant effect on the aerodynamic damping ratio where it decreases with increasing side ratio. Although the cross-wind eccentricities are found to have no significant influence on the aeroelastic effects, the along-wind eccentricities greatly influence the aeroelastic effects. Furthermore, a windward eccentricity can increase both the aerodynamic stiffness and damping ratios, whereas a leeward eccentricity can decrease these ratios.