Spectral modeling of turbulence distortion effect on cross-wind loading of high-rise buildings in wind tunnel tests

This paper mainly studies the impact of turbulence scale on unsteady cross-wind loading (CWL) on high-rise buildings (HRBs) in wind tunnel tests. Wind tunnel tests were conducted utilizing a 2:1 rectangular rigid segment pressure measurement model to analyze the influence of the scale ratio Lw/B (where Lw represents the turbulence scale in cross-wind direction and B denotes the cross-wind model size) on the unsteadiness of CWL. This investigation concentrated on the unsteady effects of CWL, encompassing both three-dimensional effects and turbulence distortion effects. The results indicate that the scale ratio Lw/B has a significant impact on the unsteady characteristics of CWL. An increase in the Lw/B ratio results in a higher peak value of the CWL spectrum and a shift toward lower frequencies. Conversely, a reduction in the Lw/B results in an increased high-frequency decay slope of CWL, due to the distortion effect. Moreover, a reduction in Lw/B results in a decrease in the spatial correlation of CWL, although it remains significantly higher than that of the cross-wind gusts. Therefore, a two-dimensional aerodynamic admittance function model to modify the distortion effects on HRBs was developed based on small-scale turbulence wind tunnel tests. Finally, a 2:1 rectangular cross section HRB model pressure measurements in the atmospheric boundary layer are conducted. The results indicate that the proposed model is highly accurate in modifying the distortion effect. Meanwhile, the applicability of the strip theory is also clarified.