Research On Mechanical Properties Of Spring-Damping Anti-Vibration Bearing And Its Application In Wind Vibration Control Of Large Cantilever Structure

The long-span spatial structure mainly uses spatial form or three-dimensional forms to resist external force.It is widely used in various landmark buildings because of its rich building modeling,good integrity and stress characteristic.The long-span spatial structure has features of light weight,low frequency,large flexibility,small-damping and low vibration frequency,so and it is sensitive to wind and has a high probability of wind damage.In order to improve the wind-resistant performance of large cantilever structure,spring-damping antivibration bearings which combine cylindrical helical springs with cylinder-type viscous damper are designed to reduce the vertical vibration.This article focuses on the mechanical properties and the key problems in the application of spring-damping anti-vibration bearings.(1)The mechanical properties of the spring-damping bearing were tested to learn about the effects of static displacement,displacement amplitude,loading frequency and loading times of the mechanical properties of bearings.The hysteric curves of the spring-damping anti-vibration bearing were calculated and fitted with Kelvin model.The research shows that the bearing has chubbiness hysteretic curve,stable mechanical properties and good energy dissipation capacity,and there is no deviation from the analog value and test values.Through the combination of the above tests and theories,grasp the basic mechanical characteristics of the spring-damping anti-vibration bearing.(2)Using wind pressure data from the wind tunnel test,the wind load of the stadium is established.The wind-induced response analysis was carried out with the finite element software Midas Gen.The displacement and acceleration response from the structural typical node with and without the bearings is compared and analyzed.The vibration reduction rate of the bearings is calculated to validate its vibration reduction effect effectively.The results showed that the effect of adding spring-damping anti-vibration bearings is obvious for controlling the wind-induced vibration response,and the maximum reduction reaches 92.16%.This paper discusses the influence of the number and layout location of the bearings to wind vibration control effect.The analysis results show that arranging the bearings on the top of the column has a better wind damping effect and properly decreasing the number of the bearings has little effect on wind damping effect.(3)Based on the response surface method,the relationship between the bearing parameters and wind-induced response was fitted.The response surface method is used to optimize the parameters of bearing for large cantilever structure.The optimal results show that when bearings are used for damping to design,their stiffness is set according to the standard that only provides support,and their viscous damping coefficient can be set according to the damping target.Aiming at large cantilever structure,local sensitivity analysis and global sensitivity analysis are used separately to study the impact of the bearing parameters on the wind-induced vibration responses.It is shown that the local sensitivity of structural wind-induced vibration response to the stiffness decrease to the increase in stiffness,as same as the viscous damping coefficient.The viscous damping coefficient of the bearing has dominant contribution to the uncertainty of wind-induced vibration response.