Wind Pressure of Low-rise Buildings Based on Wind-tunnel Numerical-simulation Test

Abstract

Based on the numerical-simulation test data from the wind tunnel, the wind-pressure characteristics of low-rise buildings with gable roofs are examined and compared to standard values under different roof slopes, eave heights and terrains. To further investigate the underlying mechanisms of variation, a numerical-simulation study was conducted for selected conditions. The results indicate that when the roof slope is less than 3:12, the negative value of the shape coefficient for the windward roof of the building can reach up to -0.89, far exceeding the code value of -0.5. It is suggested that when the slope is not larger than 3:12, the shape coefficient for the windward roof should be -0.9 and the coefficient for the leeward roof should be determined through linear interpolation within the range from -0.4 to -0.75 based on the roof's slope size. With the increase of eave height and the decrease of ground roughness, the vortex intensity of the roof and the leeward surface increases and the area proportion of high negative pressure area in the vortex influence range increases. Thus, the negative value of the shape coefficient for the roof and the leeward surface becomes larger, which is higher than the code value. It is proposed that under an eave height of 12 m, the shape coefficient for the windward roof should be -0.95. Meanwhile, those of the leeward roof, leeward surface and sidewall 2 should be -0.6 under open terrain. Keywords: Low-rise buildings, Wind-tunnel test, Wind load, Shape coefficient, Numerical simulation