Basone Francesco, Bursi Oreste S, Aloschi Fabrizio, Fischbach Günter
Engineering and Architecture Faculty, University of Enna "Kore", Viale delle Olimpiadi, 94100, Enna, Italy.
Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123, Trento, Italy.
Sci Rep. 2021 May 6;11(1):9728. doi: 10.1038/s41598-021-88984-0.
In this paper, we intend to mitigate absolute accelerations and displacements in the low-frequency regime of multiple-degrees-of-freedom fuel storage tanks subjected to stochastic seismic excitations. Therefore, we propose to optimize a finite locally resonant metafoundation equipped with massive resonators and fully nonlinear hysteretic devices. The optimization process takes into account the stochastic nature of seismic records in the stationary frequency domain; the records are modelled with the power spectral density S and modified with a Kanai-Tajimi filter. Moreover, the massive superstructure of a fuel storage tank is also considered in the optimization procedure. To optimize the nonlinear behaviour of dampers, we use a Bouc-Wen hysteretic model; the relevant nonlinear differential equations are reduced to a system of linear equations through the stochastic equivalent linearization technique. The optimized system is successively verified against natural seismic records by means of nonlinear transient time history analyses. Finally, we determine the dispersion relations for the relevant periodic metafoundation.
在本文中，我们旨在减轻多自由度储油罐在随机地震激励下低频段的绝对加速度和位移。因此，我们建议对配备有大量谐振器和完全非线性滞回装置的有限局部共振超基础进行优化。优化过程考虑了平稳频域中地震记录的随机性；这些记录用功率谱密度(S)进行建模，并用金井—田治滤波器进行修正。此外，优化过程中还考虑了储油罐的大型上部结构。为了优化阻尼器的非线性行为，我们使用了Bouc-Wen滞回模型；通过随机等效线性化技术，将相关的非线性微分方程简化为线性方程组。通过非线性瞬态时程分析，针对天然地震记录对优化后的系统进行了连续验证。最后，我们确定了相关周期性超基础的色散关系。
