Study On Influence Of Surface Roughness On Wind Pressure And Wind Load Of High-rise Building

For high-rise buildings,wind load is one of the important loads that structural design needs to consider,so the study of wind load characteristics of high-rise buildings is becoming more and more important.To improve visual effects of high-rise building,shade wind and rain and provide outdoor rest places for the residents,high-rise buildings usually set decorative,sun visor,balcony and other structures on the surface.However,domestic and foreign research mainly is about smooth wall building.China's relevant norms have not yet given the wind load design standards of high-rise building with complex wall.Therefore,this paper mainly studies the wind load characteristics of high-rise buildings with rough elements on the surface,and provides design reference for engineering practice.CFD numerical simulation is usually divided into:Renault average method,large eddy simulation method,direct solution method.The large eddy simulation method is the method of both precision and computational efficiency.Therefore,this paper uses the large eddy simulation method to solve numerically.The main contents of this paper are as follows:(1)In this paper,the method of determining wind load is summarized,and the advantages and disadvantages of field measurement,wind tunnel test and numerical simulation are described respectively.With the rapid development of computer hardware technology and the continuous improvement of the theoretical model,numerical simulation has become an important branch of structural wind engineering research field.This paper briefly introduces the relevant theories of numerical simulation,such as the basic theory of computational fluid mechanics,the algorithm of numerical calculation and the theory of large eddy simulation method.(3)Stathopoulos conducted a wind tunnel test on a high-rise building with vertical bars at the Building Aerodynamics Laboratory at the University of Concordia,Canada,and analyzed the results.In this paper,the wind tunnel test data is used,and the model is established by using the structured grid.The calculated results are compared with the wind tunnel test.It is proved that the numerical simulation carried out in this paper has certain reliability.(4)The wind tunnel tests of the high-rise buildings with three different surface roughness is carried out respectively.In this paper,the wind pressure coefficient of the test is compared and analyzed to find out the influence of surface roughness on it.The numerical simulation of the three models is carried out,and the calculation of the computational domain,the meshing,the boundary condition and the solving method are described.The simulation results are compared with the experimental values to find a better fit and the location of difference between them.And this paper analyzes the influence of rough elements on the wind field environment and the interlayer force and the whole of the building,and find the place which is influenced by the roughness and needs to be paid more attention in the wind resistance design.Which provides a certain reference value for the determination of wind load in the same kind of high-rise building design.