Non-Gaussian characteristics and extreme wind pressure of long-span roof under various approaching flow turbulences

Abstract

This study investigates the effects of different turbulences on the non-Gaussian characteristics of wind loads on a long-span roof. Wind tunnel tests of the long-span roof under different turbulences were carried out. The wind pressure characteristics, non-Gaussian characteristics and formation mechanism of wind loads were analyzed in detail. The Sadek-Simiu method was used to calculate and analyze the peak factor of the fluctuating wind pressures. The results indicated that the wind pressure characteristics of the long-span roof presented non-Gaussian characteristics that are mainly influenced by turbulence. With the increasing of turbulence, the non-Gaussian characteristics of wind loads become more and more obvious. Furthermore, the criteria for the division of Gaussian and non-Gaussian zones under six different turbulence levels are identified considering that the constraint of the Skewness-Kurtosis of the long-span roof as Ku >|Sk|2 +2. It was found that the peak factor increases with the increase of turbulences and its value ranges from 4.56 to 7.03, which is about 82.4%–181.2% higher than the stipulated value of 2.5 specified in the design code. Therefore, the value of the peak factor in the specification should be appropriately increased to ensure the safety of the long-span roof structure