复合阻尼索设计及减振性能试验研究

Design of the compound damping cable and experimental studies on structural vibration control

采用大垂度副索承担横向荷载效应,对主索进行多点弹簧悬挂,使主索保持近似直线状态,获得小张拉力下的主索最大弦向刚度;在主索上串联磁流变阻尼器和复位弹簧,开发出了复合阻尼索。采用塔结构模拟高耸结构,在塔与地面间安装跨度18m复合阻尼索,通过试验研究在不同的主索弦向刚度、主索在结构上不同的安装高度、及磁流变阻尼器不同输入电压下复合阻尼索对结构振动控制的效果。结果表明:复合阻尼索主索弦向刚度越大,其对结构减振效果越好;阻尼索的安装高度越高,其对高耸结构第一阶弯曲振动减振的效果越好;随着阻尼器阻尼系数的增大,结构附加等效阻尼比先增大,后减小,存在最优阻尼系数,使得结构获得最优减振效果。

Undertaking lateral load effect by using the large sag cable,the main cable is subjected to the multi-point spring suspension to keep it in a straight line state.As a result,the maximum string stiffness of the main cable under the small tension is obtained.The composite damping cables are developed by installing both the magnetorheological damper and reset springs on the main cable in series.Based on the tower structure for simulating the high-rise structure,as well as the span of 18 m composite damping cable installed between the tower and the ground,the effects of composite damping cable with different main cable string stiffness,the main cable installation height and the input voltage of the magnetorheological damper on the structure vibration control are investigated.The experimental results show that the damping effect of the composite damping cable is improved with the increase of the string stiffness of the main cable.The damping effect of the first order bending vibration on the high-rise structure is better with the increase of the installation height of the damping cable.With the increase of the damping coefficient of the damper,the additional damping ratio of the structure increases at first and decreases later.The optimal damping coefficient exists so that the optimal vibration control effect of the structures can be obtained.