随机激励下考虑附加刚度的粘滞阻尼器-斜拉索参数振动模型分析及控制分析  

Parametric vibration model analysis and control analysis of viscous damper stayed cable considering additional stiffness under random excitation

作　　者：向泓嘉 XIANG HongJia(Hubei Key Laboratory of Disaster Prevention and Reduction(China Three Gorges University),Yichang 443002)

机构地区：[1]防灾减灾湖北省重点实验室(三峡大学),湖北宜昌443002

出　　处：《灾害与防治工程》2021年第2期40-53,共14页Disaster and Control Engineering

基　　金：国家自然科学基金项目(51778343);2017年度防灾减灾湖北省重点实验室(三峡大学)开放基金(2017KJZ07)。

摘　　要：为了更加准确的掌握在随机激励下,粘滞阻尼器的参数设置对拉索防振的影响,建立了在随机激励下,考虑附加刚度的粘滞阻尼器-斜拉索体系参数振动模型,采用了蒙特卡洛模拟拉索的端部随机激励,建立了斜拉索伊藤型随机参数振动模型,推导了斜拉索运动方程,运用IVWstein-Platen方法离散拉索结构的振动微分方程,避免参激的扩散系数对数值格式的影响,编制程序求解了拉索结构随机振动时程,以随机轨道的角度分析拉索随机位移变化。分析了斜拉索受控前后的拉索振动位移特征,研究了高斯、线性滤波激励下,考虑附加刚度的粘滞阻尼器对于斜拉索时域、频域、统计、概率特性的影响,结果表明:位移速度相空间中红线均大于蓝色所占面积,其中线性滤波随机激励作用下相空间出现极限环,蓝色越靠近中心越集中;考虑附加刚度粘滞阻尼器影响,斜拉索的位移时程、均值、均方差均有有明显抑制,其抑制率为26.7%~38.8%,考虑粘滞阻尼器的抑制率为84.5%~95.3%。对于响应概率特性,对于高斯激励下,考虑粘滞阻尼器的拉索概率密度山峰越来越趋于陡峭,分布范围缩小;对于线性滤波随机激励下,拉索响应概率过于扁平化,振动平稳;而考虑阻尼器时,响应概率曲线过于陡峭,振动幅值集中在零区域。In order to more accurately grasp the influence of the parameter setting of viscous damper on cable anti vibration under random excitation,a parametric vibration model of viscous damper cable system considering additional stiffness is established under random excitation.Monte Carlo is used to simulate the random excitation at the end of cable,an ITO type random parametric vibration model of cable is established,and the motion equation of cable is deduced,The Milstein platen method is used to discretize the vibration differential equation of cable structure to avoid the influence of the diffusion coefficient of parametric excitation on the numerical scheme.A program is compiled to solve the random vibration time history of cable structure,and the variation of cable random displacement is analyzed from the perspective of random track.The vibration displacement characteristics of stay cables before and after being controlled are analyzed.The influence of viscous damper considering additional stiffness on the time domain,frequency domain,statistics and probability characteristics of stay cables under Gaussian and linear filter excitation is studied.The results show that the red line in the displacement velocity phase space is greater than the area occupied by blue,and there is a limit cycle in the phase space under the random excitation of linear filter,The closer the blue is to the center,the more concentrated it is;Considering the influence of additional stiffness viscous damper,the displacement time history,mean value and mean square deviation of stay cable are obviously restrained,and the inhibition rate is 26.7%〜38.8%,and the inhibition rate considering viscous damper is 84.5%~95.3%.For the response probability characteristics,under Gaussian excitation,the peak of cable probability density considering viscous damper tends to be steeper and narrower;For linear filtering random excitation,the cable response probability is too flat and the vibration is stable;When considering the damper,the response probability c

关 键 词：斜拉索 随机激励 参数振动 粘滞阻尼器 

分 类 号：TU3[建筑科学—结构工程]