An innovative variable stiffness device is proposed and investigated based on numerical simulations. The device, called a folding variable stiffness spring （FVSS）, can be widely used, especially in tuned mass dampe...An innovative variable stiffness device is proposed and investigated based on numerical simulations. The device, called a folding variable stiffness spring （FVSS）, can be widely used, especially in tuned mass dampers （TMDs） with adaptive stiffness. An important characteristic of FVSS is its capability to change the stiffness between lower and upper bounds through a small change of distance between its supports. This special feature results in lower time-lag errors and readjustment in shorter time intervals. The governing equations of the device are derived and simplified for a symmetrical FVSS with similar elements. This device is then used to control a single-degree-of-freedom （SDOF） structure as well as a multi-degree-of-freedom （MDOF） structure via a semi-active TMD. Numerical simulations are conducted to compare several control cases for these structures. To make it more realistic, a real direct current motor with its own limitations is simulated in addition to an ideal control case with no limitations and both the results are compared. It is shown that the proposed device can be effectively used to suppress undesirable vibrations of a structure and considerably improves the performance of the controller compared to a passive device.展开更多
目的研究地震作用下高压输电塔-线耦合体系纵向减震控制.方法运用有限元分析软件ABAQUS建立高压输电塔-线耦合体系的精细化模型.利用非线性时程方法分析地震作用下碰撞摆(Pounding Tuned Mass Damper)对输电塔-线体系的减震控制,并与悬...目的研究地震作用下高压输电塔-线耦合体系纵向减震控制.方法运用有限元分析软件ABAQUS建立高压输电塔-线耦合体系的精细化模型.利用非线性时程方法分析地震作用下碰撞摆(Pounding Tuned Mass Damper)对输电塔-线体系的减震控制,并与悬挂质量摆(Suspension Mass Pendulum)的减震效果进行对比分析.结果以Kobe地震作用为例,悬挂质量摆控制下输电塔-线体系塔顶位移、加速度和主材轴力峰值减振率分别为29%、23%和26%,碰撞摆控制下的峰值减振率分别为41%、29%和38%,可以看出,碰撞摆的减振效果明显优于悬挂质量摆.结论悬挂质量摆能够有效地抑制结构的不良振动,而碰撞摆的震动控制能力明显强于悬挂质量摆.展开更多
文摘An innovative variable stiffness device is proposed and investigated based on numerical simulations. The device, called a folding variable stiffness spring （FVSS）, can be widely used, especially in tuned mass dampers （TMDs） with adaptive stiffness. An important characteristic of FVSS is its capability to change the stiffness between lower and upper bounds through a small change of distance between its supports. This special feature results in lower time-lag errors and readjustment in shorter time intervals. The governing equations of the device are derived and simplified for a symmetrical FVSS with similar elements. This device is then used to control a single-degree-of-freedom （SDOF） structure as well as a multi-degree-of-freedom （MDOF） structure via a semi-active TMD. Numerical simulations are conducted to compare several control cases for these structures. To make it more realistic, a real direct current motor with its own limitations is simulated in addition to an ideal control case with no limitations and both the results are compared. It is shown that the proposed device can be effectively used to suppress undesirable vibrations of a structure and considerably improves the performance of the controller compared to a passive device.
文摘目的研究地震作用下高压输电塔-线耦合体系纵向减震控制.方法运用有限元分析软件ABAQUS建立高压输电塔-线耦合体系的精细化模型.利用非线性时程方法分析地震作用下碰撞摆(Pounding Tuned Mass Damper)对输电塔-线体系的减震控制,并与悬挂质量摆(Suspension Mass Pendulum)的减震效果进行对比分析.结果以Kobe地震作用为例,悬挂质量摆控制下输电塔-线体系塔顶位移、加速度和主材轴力峰值减振率分别为29%、23%和26%,碰撞摆控制下的峰值减振率分别为41%、29%和38%,可以看出,碰撞摆的减振效果明显优于悬挂质量摆.结论悬挂质量摆能够有效地抑制结构的不良振动,而碰撞摆的震动控制能力明显强于悬挂质量摆.
