Local wind pressures on tiny rods of complex grid structures are difficult to obtain through wind tunnel tests due to their small sizes after scaling down, resulting in a lack of data support in wind load calculations for similar structures. However, local wind pressures on tiny rods can be obtained through numerical wind tunnel simulation using full-sized models. In order to investigate the wind pressure distribution of a grid structure and the influence of grid structures on the wind load of core tubes, three different television tower models are established based on an engineering example for large eddy simulations. A turbulence inlet generator (NSRFG) is adopted in the simulations while reproducing a portion of the wind tunnel test section including the mean and fluctuating pressures for validation. The results indicate that the mean wind pressures on the intersection of rods in the windward zone of the grid structure are higher than those on adjacent rods. Distinct reductions in the mean and fluctuating wind pressure of the grid structure are found in different zones. Moreover, resultant wind load forces and bending moments in the X and Y direction of the grid structure generally exceed 70% of the total wind loads. Based on simulation results, extreme net wind pressures of the grid structure and shape coefficients of enclosed regular octagonal cross-section buildings with the grid structure are provided for reference.

Large-span open prefabricated spatial grid structures are characterized by light mass, high flexibility, low self-oscillation frequency, and low damping, resulting in wind-sensitive structures. Meanwhile, their height tends to be relatively low, located in the wind field with a large wind speed gradient and high turbulence area. Therefore, surface airflow is complex, and many flow separations, reattachment, eddy shedding, and other phenomena occur, causing damage to local areas. This paper took the Evergrande Stadium in Guiyang, China, as the research object and used the random number cyclic pre-simulation method to study its surface extreme wind pressure. Firstly, five conventional distributions (Gaussian, Weibull, three-parameter gamma, generalized extreme value, and lognormal distribution) were fitted to the wind pressure probability densities at different measurement points on the surface of the open stadium. It is found that the same distribution could not be chosen to describe the probability density distribution of wind pressure at all measurement points. Hence, based on the simulation results, the Gaussian and non-Gaussian regions of this structure were divided to determine where to apply which distribution. Additionally, the accuracy of the peak factor, improved peak factor, and modified Hermite moment model method were compared to check their applicability. Finally, the effect of roughness on the extreme wind pressure distribution on the open stadium surface was also investigated according to the highest accuracy method above. The findings of this study will provide a reference for engineers in designing large-span open stadiums for wind resistance to minimize the occurrence of wind damage.

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