Studv On Wind Load Characteristics Of Polygonal Twin-tower High-rise Buildings

Wind load is one of control loads of high-rise buildings. But the formation mechanism is complex and the influencing factors are numerous.The wind load characteristics of the polygonal twin-tower high-rise buildings are more complicated. Based on the background of the polygonal twin-tower high-rise building, research on the wind load characteristics is carried out. The main study contents and conclusions are as follows:The wind tunnel test of multi-point synchronous pressure measurement on rigid model is conducted. Spatial distribution characters of mean wind loads and local shape coefficient are investigated. It has been found that the narrow passage between the two towers forms the flow acceleration region. Relatively large negative wind pressure appears in the polygonal arc region and the shape coefficient values of measuring points increase more than those in the line segment region. The maximum negative value is greater than the standard value.Based on the wind tunnel test of fluctuating wind pressure, the fluctuating wind load characteristics of polygonal high-rise building are studied. The results reveal that narrow channel effect has certain enhancement of the fluctuating wind pressure. And the flow is separated on the corner, which leads to the greatly improvement of the fluctuating wind pressure. For the wind resistant design of retaining structure, a single value of local shape coefficient according to the specification is unreasonable. It is advised that the fluctuating wind pressure extremum is calculated by statistic extreme method and considering the internal pressure according to the specification.Compared with the wind load of twin-tower high-rise buildings with the smoothing and the regular sharp hexagonal sections, the local shape coefficient value in the arc region is dangerous according to the specification and that of line segment region is partial safety. Although the corner smoothing results in the increasement of local wind pressure coefficient, the overall load is greatly decreased. The polygonal corner is suggested to be smoothed, but the arc region must be strengthened.