Study On Wind-induced Interference Effects Of Long-span Dome Roof Structure

long-span dome roof structures have been widely applied in public buildings.However,long-span dome roof structures are wind-sensitive and the wind loads are the main control load of these structures.The wind pressure distribution of the long-span dome roof structure is greatly affected by the flow field form,the structure shape and surrounding buildings.However,there is no reference for this issue in the current design regulation.Especially,the urban buildings are denser,and the aerodynamic interference on the wind pressure between surrounding buildings and long-span dome roofs become more significant.Therefore,it is necessary to study the interference effects between surrounding buildings and long-span dome roof structures.Based on the wind tunnel test and the computational fluid dynamics(CFD)numerical simulation method,this thesis systematically studies the wind-induced interference effect of the long-span dome roof structure.The main contents are as follows:1.The wind tunnel test are performed for an isolated long-span dome roof structure and two cases of interfering buildings with different spacing ratios,two cases of different height ratios,two cases of different width ratios to study the interference effect of long span dome roof structure.The wind pressure distribution of long span dome roof structures under different cases were analyzed and compared to illustrate its wind pressure distribution characteristics and interference characteristics.2.The wind-induced interference effects of long-span dome roofs are studied for the same case through the numerical simulation.The accuracies of numerical results are verified through wind tunnel test.Then,based on the Fluent software,the wind-induced interference effects of long-span dome roofs are studied for 4 wind direction angles,7 types of spacing ratios,6 types of height ratios,4 types of width ratios for analyzing wind-induced interference of long-span dome roof structure in this paper.By comparison,it is found that long-span dome roof structure mainly has negative wind pressure on the roof;the wind pressure distribution is arc-shaped and the worst wind pressure area on the roof occurs around the center of the roof;.Under the multi-wind direction,where the width ratio has the greatest influence on the interference effect of roof,the spacing ratio influence is second,and the height ratio is the smallest.When the spacing ratio is lager than 1.5,the interference effect of the surrounding buildings gradually decreases;and when the height ratio and the width ratio islarger than 1.6 and 0.6,the interference effect become gradually constant.3.According to the current wind load code,the interference coefficient(I)is proposed to give a reference for wind resistance design.Compared with regulation of the wind load code,the wind pressure in the central area of roof under the worst wind direction will increase 1.6times,1.5 times,2.0 times with the influence of spacing ratio,height ratio,width ratio.The edge area is the most affected by the interference effect,so both areas need to be considered specially.