Abstract Nonlinear fluid viscous dampers have been widely used in energy-dissipating structures due to their stable and high dissipation capacity and low maintenance cost. However, the literature on stochastic optimization of nonlinear viscous dampers under nonstationary excitations is limited. This paper is devoted to the stochastic response and sensitivity analysis of large-scale energy-dissipating structures equipped with nonlinear viscous dampers subjected to nonstationary seismic excitations. The analysis procedure is developed in the frame of the equivalent linearization method (ELM) in conjunction with the explicit time-domain method (ETDM). The equivalent linear system and the corresponding statistical moments of responses at a specific time instant are first obtained through a series of stochastic response analyses of the linearized systems. Then the sensitivities of the statistical moments of responses are determined via a series of stochastic sensitivity analyses of the equivalent linear system at the corresponding time instant. The above two iterative procedures are facilitated at high efficiency using ETDM with explicit formulations of the statistical moments of responses and the sensitivities of the statistical moments. This process is repeated for different time instants, and the time histories of the statistical moments and their sensitivities can be obtained. The stochastic response and sensitivity results are further utilized to conduct the stochastic optimal parametric design of the nonlinear viscous dampers. A one-storey building model equipped with a nonlinear viscous damper is analyzed to demonstrate the accuracy of the proposed method, and a suspension bridge with a main span of 1200 m equipped with 4 nonlinear viscous dampers is further investigated to illustrate the feasibility of the proposed method for stochastic optimal design of large-scale structures.

中文翻译：

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基于显式时域法的高效等效线性化技术对非线性黏滞阻尼器耗能结构随机灵敏度分析

摘要 非线性流体粘性阻尼器以其稳定、高耗散能力和低维护成本等优点在消能结构中得到广泛应用。然而，关于非平稳激励下非线性粘性阻尼器随机优化的文献是有限的。本文致力于非线性粘性阻尼器的大型耗能结构在非平稳地震激励下的随机响应和灵敏度分析。分析程序是在等效线性化方法 (ELM) 和显式时域方法 (ETDM) 的框架内开发的。首先通过对线性化系统的一系列随机响应分析得到等效线性系统和特定时刻响应的相应统计矩。然后通过等效线性系统在相应时刻的一系列随机灵敏度分析来确定响应的统计矩的灵敏度。使用具有响应统计矩和统计矩灵敏度的显式公式的 ETDM，可以高效地促进上述两个迭代过程。在不同的时刻重复这个过程，就可以得到统计矩的时间历程和它们的灵敏度。进一步利用随机响应和灵敏度结果进行非线性粘性阻尼器的随机优化参数设计。对安装非线性黏滞阻尼器的单层建筑模型进行了分析，验证了该方法的准确性，并进一步研究了主跨为 1200 m 的带有 4 个非线性黏滞阻尼器的悬索桥，以说明该方法的可行性。大型结构随机优化设计方法[J].