Numerical Simulation Study Of Wind Load On Low-Rise Gable-Roofed Building

As one of the major natural disasters,the consequences of the typhoon are very serious.The coastal areas of China are often hit by typhoons,resulting in huge economic losses.The previous wind disaster survey results show that more than half of the losses are caused by lowrise buildings,especially the damage to the roof structure.In the aspect of wind-resistance research,most of the wind engineering research in the world is mainly focused on high-rise buildings and large span bridges.There are few studies on the wind load characteristics of lowrise building.Therefore,it is of great practical significance to study the wind-resistance of lowrise buildings.The Fluent software and RNG turbulence model were used to study the wind pressure on the roof of the low-rise buildings in this paper.The geometric size of the model is 24m×16m×8m,and the roof slope angle is 4.8°.The results of numerical simulation and wind tunnel test were compared and the results showed that the numerical simulation method in this paper can accurately reflect the distribution of wind pressure on the roof of low-rise buildings.On this basis,this paper studied the following aspects of low-rise buildings.(1)The effects of different wind direction angles and slope angles on the wind pressure distribution of low-rise buildings were studied.The results show that the wind direction angle has a great influence on the wind pressure of the roof.The entire roof is affected by suction under the influence of the flow.The windward eaves and the windward corners are unfavorable wind-resistance positions,where the negative pressure is very large.The influence of slope angle on the wind pressure of the roof is related to the wind direction.Under the wind direction of 0°,the influence of slope angle on wind pressure is not obvious.Under the oblique wind direction and the wind direction of 90°,the slope angle has great influence on the ridge of the leeward roof.The wind pressure on the ridge of the leeward roof reaches the extreme at the angle of 15°~25°.Meanwhile,the ridge of the leeward roof becomes an unfavorable windresistance position.(2)The effects of different mountain arrangement on the wind pressure distribution of lowrise buildings were studied.The results show that the four types of mountain layout in this paper have a great impact on the wind pressure distribution of low-rise buildings,and the influence of the house with the mountain behind is much larger than that of the house without the mountain behind.Besides,there is little influence on the shape coefficient of the roof in the range of the spacing ratio we adopted in this paper.(3)The effects of different forms of parapet on the wind pressure distribution of low-rise buildings were studied.The results show that different forms of the parapet can reduce wind pressure at the windward eaves and the windward corners in different degrees.Besides,the low height of the parapet(<0.4m)has the potential to increase the pressure at the corner.(4)Based on the study of the wind load characteristics of the single low-rise building,the effects of the surrounding buildings on the wind pressure distribution of low-rise buildings were studied.The study objects are two low-rise buildings with the same shape.The results show that the influence of the wind pressure on the roof is weakened with the increase of the spacing ratio under the three different forms of house layout.At last,the reasonable layout form of lowrise buildings is summarized.