斜拉索风雨激振的形状记忆合金半主动控制数值模拟分析

斜拉索风雨激振的控制是斜拉桥工程的关键技术难题之一。本文利用轴向设置的形状记忆合金(ShapeMemory Alloy,SMA)作动器,对斜拉索的风雨激振进行了半主动控制数值模拟分析,控制规则采用KOBORI开关控制。数值分析结果表明,SMA半主动控制可有效的控制拉索的风雨激振;SMA的设置长度及初始的应变大小对控制效果有较大的影响,SMA长度越长,初始应变越大,其控制效果越佳。对由SMA控制引起的拉索张力变化做了分析,其张力的变化很小,在可接受的范围内。研究表明,SMA作动器在参数非理想时控制效果可能有所降低,但控制的稳定性良好。

Control of Rain-Wind-Induced Cable Vibration by Using Shape Memory Alloy

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.