The Wind-Load Calculation Of Single-Layer Spherical Shell And The Impact Analysis Of Wind Vibration Coefficient

The influence of wind vibration on reticulated shell is not less than that on high-rise structures and long-span bridges. In most cases the wind load becomes the control load. But the calculation of wind vibration response has strong theories and heavy workload, and its application is restricted in practical engineering. Such the influence of wind load on reticulated shell has become urgent problem to be solved.The main research contents and achievements of this paper are shown as following:(l)The time-history analysis of structures under total wind load and under combined action of average wind and fluctuating wind are conducted respectively. The conclusion that the effect of pure fluctuating wind on structures' wind-induced response should not be ignored in computational process can be obtained by comparing the result of displacement, axial force and wind vibration coefficient.(2)Discuss the change law of nodal displacement, element force and wind vibration coefficient of two conditions respectively. One is that all of the structure nodes bear certain same time-history wind load, and the other is that all of the structure nodes bear its time-history wind load itself. The results indicate that the wind-induced response of the structure is not significant when the nodal wind load changing in the first condition, but the response is significant in the second condition. The wind-induced response is bigger in the second condition.(3)The influence of changing the stiffness and rise-span ratio of the structure on wind vibration coefficient is discussed. The results show that the integral wind vibration coefficient decreases in the wake of the increase of stiffness and rise-span ratio of the structure, and the integral wind vibration coefficient has a linear relationship with rise-span ratio. For the single-layer latticed domes with rise-span ratio 0.25, the singular points of wind vibration always occur on the nodes and the ring directionin elements on the second circle inward the edge. The positions of the singular points of wind vibration are changing with the rise-span ratio changing. Getting rid of the wind vibration coefficient that are greater than 5, the integral wind vibration coefficient with the guarantee rate of 95 percent is calculated. When rise-span ratio is 0.25, the integral wind vibration coefficient of displacement is 4.5595 and the integral wind vibration coefficient of internal force is 4.2039. According to the analysis of this paper, comprehensively considering the effects of stiffness and rise-span ratio, the integral wind vibration coefficient of single-layer sphericalshell can be adopted 4.6 securely. The article provides certain basis for wind-resistant design of long-span spatial structures and calculates wind vibration coefficient of single-layer latticed domes. Then points out the defects and problems that remains to be solved in the wind-induced responseanalysis of single-layer latticed domes .