Optimal tuning and assessment of inertial dampers with grounded inerter for vibration control of seismically excited base-isolated systems
Optimal tuning and assessment of inertial dampers with grounded inerter for vibration control of seismically excited base-isolated systems
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DOI：
10.1016/j.engstruct.2019.05.091
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发表时间：
2019-10-01
影响因子：
5.5
通讯作者：
Pietrosanti, Daniele
中科院分区：
文献类型：
--
作者：
De Angelis, Maurizio;Giaralis, Agathoklis;Pietrosanti, Daniele
本文提出了一种理想接地线性惯性器的概念，在不增加被动线性调谐质量阻尼器（TMD）质量的情况下，通过其惯性特性赋予TMD附加惯性，以减小基础隔震结构（BIS）的侧移需求。最佳调谐质量阻尼器惯性（TMDI）的设计参数的数值确定，以最大限度地提高能量耗散下的平稳白色噪声支持激励的TMDI。这些最佳设计的TMDI配备BIS的性能进行评估固定的白色和有色噪声激励，以及为四个记录的地震加速度地面运动（GM）具有不同的非平稳频率的内容。据发现，对于固定的质量比，列入接地惯性器显着减少二次质量位移和冲程为所有考虑的激励，而它明显改善BIS位移的要求，除了一个特定的情况下，近故障加速度图的特点是早期到达的高能量低频脉冲捕获在其小波频谱图。更重要的是，它导致进一步减少BIS加速度的需求，除了有色噪声激励，其中一个微不足道的增加被注意到。随着惯性和BIS阻尼比的增加，惯性器的积极作用饱和，表明小惯性值在具有低固有阻尼的BIS的振动抑制中更有效。总之，建议将联合收割机低阻尼隔震层与大惯性和低次级质量TMDI相结合。
In this paper, the concept of an ideal grounded linear inerter, endowing supplemental inertia to passive linear tuned mass-dampers (TMDs) through its inertance property without increasing the TMD mass, is considered to reduce lateral displacement demands in base isolated structural systems (BISs). Optimal tuned mass-damper-inerter (TMDI) design parameters are numerically determined to maximize energy dissipation by the TMDI under stationary white noise support excitation. Performance of these optimally designed TMDI-equipped BISs is assessed for stationary white and colored noise excitations as well as for four recorded earthquake acceleration ground motions (GMs) with different non-stationary frequency content. It is found that for fixed mass ratio the inclusion of the grounded inerter reduces significantly secondary mass displacement and stroke for all considered excitations while it improves appreciably BIS displacement demands except for the particular case of a near-fault accelerogram characterized by early arrival of a high-energy low-frequency pulse as captured in its wavelet spectrogram. More importantly, it leads further to reductions to BIS acceleration demands with the exception of colored noise excitation for which an insignificant increase is noted. The positive effects of the inerter saturate with increasing inertance and BIS damping ratio demonstrating that small inertance values are more effective in vibration suppression of BISs with low inherent damping. Overall, it is recommended to combine low damping isolation layers with large inertance and low secondary mass TMDIs.