采用不同轨道形状的轨道非线性能量阱减振鲁棒性分析

轨道非线性能量阱(track nonlinear energy sink,轨道NES)是一种具有较高频率鲁棒性的非线性质量阻尼器,但NES的非线性特点导致其减振性能对输入能量大小较敏感。为了改善其能量鲁棒性,分析考察了三层框架主体结构附加不同质量阻尼器时的响应,包括不同轨道形状的轨道NES以及用于对比的一型NES(typeⅠnonlinear energy sink)和调谐质量阻尼器(tuned mass damper,TMD)。结果表明,采用不同轨道形状的轨道NES均展现出优越的减振性能;其中使用三阶多项式轨道形状的轨道NES同时具备较高的频率鲁棒性和能量鲁棒性,对于地震作用下有可能发生损害的结构,轨道NES较TMD和一型NES展现出更强的减震控制性能。

Robustness study on track nonlinear energy sinks with different track shapes for response reduction

Track nonlinear energy sink is a type of nonlinear mass dampers with high robustness against changes in structural frequency. The effectiveness of NES is found to be dependent on the magnitude of input energy. In order to improve its energy robustness, the responses of a three-story frame model with a track NES, a type I NES, and a tuned mass damper (TMD) attached respectively are analyzed. Polynomials of difference orders are considered for the track shape. Results show that the three-order-polynomial track NES exhibits stronger robustness against changes in input energy level than the other track NESs considered. The three-order-polynomial track NES is further compared with a type I NES and a TMD when subjected to seismic excitations, showing great potential for seismic response reduction.