Effects of Surface-Attached Vertical Ribs on Wind Loads and Wind-Induced Responses of High-Rise Buildings

Facade design tends to be diverse with increasing requirements for architectural functions in modern high-rise buildings, leading to various aerodynamic roughness conditions of the building surface. A typical practice is setting vertical ribs on the building facade. This study aims to clarify the effects of vertical ribs on the wind loads and wind-induced responses of high-rise buildings. The models with four vertical rib configurations were tested in the open and suburban exposures using the High-Frequency Force Balance (HFFB) technique in a wind tunnel. The base overturning moments and corresponding responses are demonstrated and compared between models and exposures. Results show that the vertical ribs with a relative width of 4% can not only reduce the mean force coefficients in the along-wind direction but also attenuate the cross-wind vibration by disrupting the regular vortex shedding. Moreover, the half-distributed and full-distributed rib configurations have almost indistinguishable benefit, indicating that the ribs in the corner region of the building facade play a dominant role in reducing the wind-induced responses. Although the cross-wind responses of the building would be less severe in the suburban exposure than those in the open exposure, the reduction rate of the wind-induced responses by the vertical ribs remains almost unchanged.