【摘要】 由于拉索具有极大的柔性,相对较小的质量,以及非常低的阻尼,其对风荷载及交通荷载引起的振动十分敏感。最近的研究方向也转向了对索振动使用电/磁流变阻尼器的半主动控制。本文通过在靠近下端锚固点的轴垂直方向设置电流变阻尼器来减缓拉索振动。实验中,我们对实际索结构中143m长的索取1/12的模型比,也就是建立一个12m长的索模型。设计了一个电流变阻尼器,在不同的激振力幅值和不同的使用电压条件下,对拉索-阻尼器系统的非线性振动特性进行了实验研究。最后计算了索控制后的振动衰减效果。更多还原

【Abstract】 Stay cables are susceptible to vibration under wind and traffic loading due to their large flexibility,relatively small mass and very low inherent damping.A recent research interest has been given to the semi-active control of cable vibration by using electro-rheological(ER) and magneto-rheological(MR) fluid dampers.This paper reports an experimental study on vibration mitigation of a stay cable by installing an electro-rheological(ER) damper in the transverse direction near the lower anchorage.A 12m-long stay cable specimen,which is a 1∶12 scale model of a 143m-long prototype cable in an actual cable structure,is established for the experimental study.A specific low-force ER damper is constructed for this purpose.By exciting the cable at a point near the upper anchorage,the nonlinear frequency response curves of the cable-damper system under different exciting force amplitudes and applied voltage levels are obtained.更多还原