To ensure the safe operation of the gate dam and to prevent accidents

the permutation entropy (PE) algorithm is used to monitor the operational status of the gate dam. A gate being the research object

and its flow induced vibration data by each measuring point of the gate dam are obtained. Then

the improved variational modal decomposition (IVMD) method is used to denoise the original signals from different measuring points under different operation conditions and extract the effective operational feature information of the structure. Followed

the feature information of each measuring point at the data level are fused by using variance contribution rate and the subsequence entropy values of the fused data are calculated by permutation entropy method. By analysis of the entropy characteristics of different vibration states

online monitoring of structural vibration state is realized. The results show that the permutation entropy method can not only comprehensively extract effective information of the structure

but also present the vibration state of the structure in a relatively intuitive form. Furthermore

the calculation process is simple and efficient

which can provide reference for the safe operation and online monitoring of gate dams.