-
公开(公告)号：US20200074221A1
公开(公告)日：2020-03-05
申请号：US16342948
申请日：2018-03-28
发明人： Tinghua YI , Xiaomei YANG , Chunxu QU , Hongnan LI
摘要： Structural health monitoring relating to an automatic method for estimating structural modal parameters by clustering. The structural modal parameters from state-space models are calculated in different orders by Natural Excitation Technique in combination with Eigensystem Realization Algorithm According to the characteristics that physical modes are those with high similarity and stably appearing at different orders while spurious modes are those with little similarity and unstably appearing at different orders, the modal dissimilarity between two nearest modes in consecutive order are considered as feature of the mode in the lower order. Then, features of modes are used in fuzzy C-means clustering to adaptively acquire the stable cluster where modes are with high similarity. Finally, Hierarchical clustering is used to group the stable modes with identical modal parameters together and thus each physical mode can be obtained.
-
2.发明申请公开(公告)号：US20200284687A1
公开(公告)日：2020-09-10
申请号：US16479730
申请日：2019-03-01
发明人： Tinghua YI , Xiaomei YANG , Chunxu QU , Hongnan LI
摘要： A method for automatically detecting the free vibration response segment of the high-speed railway bridges after trains passing. First, pre-select the test response sequence to be decomposed based on the maximum of the time instants corresponding to the absolute maximums of the response vectors at various measuring point. Then, Extract the single-frequency modal response from the test response by the iterative variational mode decomposition and fit the envelope amplitude of the modal response by Hilbert transform. Finally, the vibration features at each time instants are marked as decay vibration or non-decay vibration. The longest structural response segment that meets the decay vibration features is determined as the detected free vibration response segment for modal identification. This invention can effectively detect the free vibration data segment without human participation, which is of great significance for the real-time accurate modal analysis of high-speed railway bridges.
-
公开(公告)号：US20200033226A1
公开(公告)日：2020-01-30
申请号：US16342954
申请日：2018-03-12
发明人： Tinghua YI , Xiaomei YANG , Chunxu QU , Hongnan LI
IPC分类号： G01M5/00
摘要： Structural health monitoring relating to an automatic method for tracking structural modal parameters. First, Natural Excitation Technique is used to transform the random responses into correlation functions and Eigensystem Realization Algorithm combined with the stabilization diagram is used to estimate modal parameters from various response segments. Then, modes from the latter response segment are classified as traceable modes or untraceable modes according to correlations between their observability vectors and subspaces of the existing reference modes. Final, traceable modes will be grouped into specified clusters with the same structural characteristics on the basis of maximum modal observability vector correlation and minimum frequency difference. Meanwhile, union of the untraceable modes and existing reference modes are updated as the new reference modes which can be applied into the next tracking process. This can track the modal parameters automatically without artificial thresholds and the specified reference modes.
-
公开(公告)号：US20200065438A1
公开(公告)日：2020-02-27
申请号：US16342929
申请日：2018-03-27
发明人： Tinghua YI , Xiaomei YANG , Chunxu QU , Hongnan LI
摘要： Structural health monitoring relating to a real-time tracking method for structural modal parameters. The Natural Excitation Technique transforms structural random responses into free decaying responses used to calculate structural modal parameters by the Eigensystem Realization Algorithm combined with the stabilization diagram. Considering influence of environmental excitation level on the number of identified modes, the reference mode list is formed by union of modes obtained from response sets in a day. Then the modes can be tracked automatically according to rules of minimum frequency difference and maximum Modal Assurance Criterion (MAC). To avoid mode mismatch problem caused by absence of threshold, frequency differences and MACs between all modes from the latter response set and all reference modes are calculated and the mode will be tracked into the cluster corresponding to the specified reference mode only in the case that their frequency difference is smallest and the MAC is largest.
-
-
-
搜索结果
4 条记录 (耗时 0.011 秒)