Blowing sand flow profiles with different particle sizes and blowing sand load characteristics on low-rise buildings

To obtain blowing sand flow profiles with different particle sizes and then assess blowing sand loads on buildings, we simulated blowing sand climates with three types of particle sizes respectively and performed the overall force tests for low-rise buildings by a blowing sand tunnel. We found that all particle concentration profiles reveal an exponential decline. The particle concentrations with coarse sand bed, fine sand bed and mixed sand bed increase successively with increasing experimental airflow velocity, and their ability to weaken airflow velocities and enhance turbulence characteristics also increase correspondingly. Wind loads in blowing sand climates are smaller than those in wind fields free from impurities, and wind loads in coarse particle, fine particle and mixed particle flow fields decrease successively, but impact loads of particles and the ratio of blowing sand loads to wind loads increase successively. Compared with airflow free from impurities, the average shear coefficients for structures in coarse particle flow, fine particle flow and mixed particle flow increase by 3%similar to 5%, 7%similar to 10%, and 11%similar to 14%. Blowing sand flows could increase pulsating shear coefficients for structures when the experimental airflow velocity is below 16.68 m/s, but blowing sand flows reduce pulsating shear coefficients for structures when the experimental airflow velocity exceeds 16.68 m/s. To ensure structural safety, the blowing sand resistance design for structures should consider both impact loads and wind loads.