Wind pressure distribution, non-Gaussian characteristics, and conical vortices of a large-span roof with variable arc angles

Understanding the characteristics and mechanism of wind pressure on long-span structures is important for structural design. In this study, the wind pressure distribution, non-Gaussian characteristics, and conical vortices of a typical large-span roof with variable arc angles were studied using wind tunnel tests on pressure measurements. The results indicate that the mean, the standard deviation(STD), and the negative extremum of the wind pressures on the corners of the roof are the most unfavorable when the corners are windward, and the values are related to arc angle. Additionally, the non-Gaussian characteristics of the roof are clear, the probability that the absolute value of skewness is greater than 0.25 exceeds 70%. The most unfavorable peak factors at the edge of the roof were larger, and they gradually decreased from the outside to the inside. Under the action of typical conical vortices, the mean, STD, skewness, and kurtosis values of wind pressures exhibit the distribution characteristics of “conical mountains,” and the wind pressures between the vortex axis, reattachment line, non-Gaussian rays, and along-wind axis varied between weak non-Gaussian (negative), Gaussian, stronger non-Gaussian (negative), and weak non-Gaussian (positive). The conical vortices exhibited stronger vortex shedding , and its energy was attenuated in the radial direction . • The research highlights in this paper are listed as following: • Strong suction at the corners is produced by the conical vortex action under oblique wind. • Airflow separation and conical vortex induce special Non-Gaussian distribution characteristics of wind pressure. • The evolution of conical vortex cause the corresponding changes of the distribution of wind pressure and energy. • The wind pressure distribution and conical vortex are significantly correlated with the included angle of the corner of roof.