Study On The Wind-induced Interference Effect Of Spherical Shell Structures

Wind load is an important factor affecting the design of various types of large-span structural roofs,and the interference effect induced by domes often makes the wind field more complex and causes the structure to behave differently from the single dome under wind loads.In this paper,the wind-induced interference effects of spherical shells under three typical arrangements(line type,regular triangle type and regular quadrilateral type)are studied by wind tunnel test technology and numerical simulation technology.The main works are presented as follows:(1)wind tunnel test technology is used to consider the interference effect of the spherical shell group in three typical arrangements(line type,regular triangle type and regular quadrilateral type),three different spacings(l=R/3,R/2,R,R represents the radius of the shell),and various wind directions.Indicators such as the overall lift force coefficient(CF)and local interference factor(IF)are used to evaluate the interference effects of different arrangement types of groups.The result shows:Spherical shells are more sensitive to changes in different arrangement and wind direction angle,but less sensitive to changes in spacing.Due to the influence of group interference,the maximum positive symmetrical overall wind load may be magnified by about 40%,and the anti-symmetrical overall wind load may be multiplied.(2)By using the numerical statistical analysis methods such as comparing the overall eigenvalues and fitting the probability distribution of discrete points,the wind pressure data from the wind tunnel test are processed,and then the different influencing factors are analyzed and compared.The result shows:In general,the cluster-type arrangement has greater advantages than the line-type arrangement in the resistance to wind-induced static loads.(3)The full-scale model is established by computational fluid dynamics numerical simulation method,and the shear stress transport turbulence model is used to analyze.A set of solving parameters suitable for the problem is determined,and reasonable simulation results are presented.And the open and closed states of the spherical shell top skylight are analyzed and compared,the research demonstrates:the result is closer to the wind tunnel test when top skylight is closed.(4)Based on the results from the wind tunnel test,CFD numerical simulation of three types of spherical shell groups in typical wind direction angle is carried out to further explore the influence of group wind-induced interference effect.Through the analysis of flow field and streamline in the computational domain,the internal mechanism of wind-induced interference effect under specific conditions is revealed.The result shows that the effect of Reynolds number is eliminated in CFD,more details of wind field are reproduced,and the local wind pressure changes in certain areas of the spherical shell surface.