Semiactive control of rain-windinduced cable vibration is simulated by using Shape Memory Alloy（SMA） as actuator.The SMA actuator is in series with cable at the anchorage.The control rule is Kobori’s Switch/off control.The numeric simulation results show that SMA can control rain-wind-induced cable vibration effectively.The influence of the length and the initial strain of SMA actuator are discussed.The more length and more initial strain is

the better control efficiency is.The change of cable force by SMA actuator is also calculated

and it is considerable small and under an acceptable level.The results show that although the control efficiency decreases in some degree for some nonideal cases

the negative control phenomenon does not happen at all simulated cases.