基于非线性黏滞阻尼器的输电塔减震控制研究

Seismic Vibration Control of Transmission Tower with Nonlinear Fluid Viscous Dampers

随着国家电网“西电东送”战略的落实和推进,大量输电塔不断投入使用,由于普遍采用钢结构,阻尼比较小,在强震作用下振动剧烈。为研究速度型黏滞阻尼器对输电塔结构的减震控制效果,本文利用SAP2000软件建立输电塔的三维有限元模型,并进行非线性动力时程分析,分析了黏滞阻尼器安装位置、速度指数和阻尼系数对输电塔峰值动力响应、阻尼器滞回曲线和能量耗散特征的影响机制和程度。结果表明:黏滞阻尼器安装位置对输电塔的减震效果有较大影响,应将其安装于塔身底部相对速度较大的位置;随着速度指数的减小和阻尼系数的增大,输电塔峰值动力响应和输入能量的减震率逐渐增大;相对于增大阻尼系数,减小速度指数具有更好的减震控制效果和经济性,同时还能有效抑制输电塔结构的动能和势能响应,可在实际工程中优先考虑。

With the promotion and implementation of the“West-To-East Power Transmission Project”,a large number of transmission towers have been put into use.Due to the widespread use of steel structure,the damping ratio of transmission tower is relatively small,and the vibration may be intense when subjected to strong earthquakes.In order to study the vibration control effect of velocity-dependent viscous dampers,SAP2000 is used to establish the three-dimensional finite element model of transmission tower and carry out the nonlinear dynamic time history analysis.The influence mechanism and degree of installation scheme,velocity index and damping coefficient of fluid viscous dampers on the peak dynamic response,hysteresis curve and energy dissipation characteristics of the transmission tower are analyzed.The results show that the installation position of fluid viscous dampers has great influence on the vibration control of transmission tower,which should be installed at the bottom of tower body with high relative vibration velocity.With the decrease of velocity index and the increase of damping coefficient,the vibration reduction ratios of peak dynamic response and input energy increase gradually.However,compared with increasing the damping coefficient,reducing the velocity index has better vibration control effect and economy,and can also effectively suppress the kinetic energy and potential energy response of transmission tower,which should be given priority in practical engineering.