Study on the sandstorm load of low-rise buildings via wind tunnel testing

Abstract

In order to investigate the influence of sandstorms on the base shear of low-rise buildings, a wind tunnel was used to simulate the flow field of sandstorms. The results showed that the sand concentration profile decreased exponentially when the wind speed was low. As wind speed increased, the sand concentration decreased with height from 0 to 0.2 m and increased with height from 0.2 to 0.5 m. The ability of moving sand particles to weaken wind speed and enhance turbulence intensity was directly related to the sand concentration profile. For buildings in a sandstorm, with the increase in sand concentration, wind load decreased, while the impact load and ratio of sandstorm load to wind load increased. The mean base shear coefficient of buildings in the flow fields of an ordinary sandstorm, moderate sandstorm and strong sandstorm increased by 4–5%, 8–10% and 12–14% respectively as compared with wind without particles. The effect of moving sand particles on the fluctuating base shear of low-rise buildings depended on wind speed and sand concentration. When wind speed was below 10.34 m/s and sand concentration was below concentration 2, the sandstorm increased the fluctuating base shear coefficient of buildings, and the enhancement effect increased with concentration; once the sand concentration exceeded concentration 2, the enhancement effect was weakened. When wind speed exceeded 10.34 m/s, the sandstorm reduced the fluctuating base shear coefficient of buildings.