研究了利用支承轴向移动对小垂度索振动实施主动控制的方法 ,对出现的不可控模态运动给出了物理解释 ,探讨了在索上附加阻尼器对不可控模态运动的影响。利用支承轴向移动对小垂度索自由振动实施主动控制进行了数值仿真研究 ;对在索上附加的阻尼器不可控模态运动的影响进行了数值仿真研究 The method of controlling the vibration of small sag cable by the axial movement of the support is studied. The physical explanation of uncontrollable mode motion is given. The influence of the additional damper on the uncontrollable mode motion is also discussed. The numerical simulation study on the active control of the free vibration of the small vertical cable is carried out by using the axial movement of the support. The numerical simulation of the influence of the uncontrollable modal motion of the additional damper on the cable is carried out