Substructure identification is an effective decentralized structural health monitoring approach for large civil structures. Previously, the authors proposed a loop substructure identification method for shear structures, which utilized the dynamic equilibrium of a non-top-floor substructure to formulate a loop identification sequence (LIS), directly estimating the substructure's parameters by only using four structural acceleration responses. However, it was found that the LIS is conditional converged. To ensure the LIS's convergence, two different methods were previously investigated, but both methods have their limitations and may not guarantee satisfactory identification results under certain circumstances. In this paper, some virtual control systems (VCSs) are introduced into the loop substructure identification. The VCS is a self-balanced system, consisting of some virtual control devices and the self-balanced forces. The virtual control devices are combined with the substructure to form a controlled substructure that is used to replace the original substructure in the loop substructure identification. An in-depth error analysis of the VCS-based loop substructure identification was conducted herein, showing that the carefully designed VCS can tune the dynamics of the controlled substructure so that the convergence of the LIS can be easily achieved. Furthermore, a robust two-step design strategy is proposed to obtain the optimal VCS's parameters with uncertain structural parameters. Finally, the numerical simulation study on a 20-story shear building and the shake table tests on a five-story bench-scaled structural model were conducted to verify the effectiveness of the designed VCS to improve the convergence and identification accuracy of the LIS.

中文翻译：

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具有虚拟控制系统的剪切结构的分散回路子结构识别

子结构识别是一种有效的分散式结构健康监测方法，适用于大型土木结构。此前，作者提出了一种剪切结构的循环子结构识别方法，该方法利用非顶层子结构的动态平衡来制定循环识别序列（LIS），仅使用四个结构加速度响应直接估计子结构的参数。但是，发现 LIS 是条件收敛的。为了保证 LIS 的收敛性，之前研究了两种不同的方法，但两种方法都有其局限性，在某些情况下可能无法保证令人满意的识别结果。在本文中，一些虚拟控制系统（VCS）被引入到回路子结构识别中。VCS是一个自平衡系统，由一些虚拟控制装置和自平衡力组成。虚拟控制装置与子结构结合形成受控子结构，用于在循环子结构识别中替代原来的子结构。本文对基于 VCS 的回路子结构识别进行了深入的误差分析，表明精心设计的 VCS 可以调整受控子结构的动力学，从而轻松实现 LIS 的收敛。此外，提出了一种稳健的两步设计策略，以获得具有不确定结构参数的最佳 VCS 参数。最后，