An improved pca damage detection method under the space-time window

Abstract

The invention discloses an improved PCA damage detection method under a space-time window. First, numerical simulation or experimental means are used to determine the spatial influence ranges corresponding to the damage at different positions under various working conditions where the damage is at different spatial positions. Then determine the structural space area sensitive to damage, that is, the space window; secondly, determine the time window related to the external load cycle according to the PCA principle; finally, after determining the time window and space window, use the PCA method for all measuring point data in the space window , using eigenvectors as monitoring indicators, real-time damage monitoring and damage location. The method of the invention performs PCA analysis on the structural response within a limited time and space window, thereby improving the accuracy and sensitivity of damage identification, and can use long-term structural monitoring data to perform damage identification on long-span solid bridges or other structures.

Description

technical field [0001] The invention relates to the technical field of structural damage identification, in particular to an improved PCA damage detection method under a time-space window. Background technique [0002] The goal of structural health monitoring is to correctly assess the safety status of the structure by obtaining the response information of the structure in real time. Under the action of long-term environmental factors, traffic loads, and natural disasters, the structure may be damaged to varying degrees, which will cause changes in the mechanical response of the structure, such as natural frequency, strain, and displacement. However, when the damage degree is small or the damage location is far away from the sensor, the response information obtained directly through the monitoring system sometimes does not change significantly, so the original data cannot be directly used to correctly diagnose the health status of the structure. In this case, it is necessar...

AI Technical Summary

Problems solved by technology

However, this method uses the PCA method to analyze the data of all measuring points uniformly, ignoring the fact that the response of measuring points far away from the damaged area is not sensitive to damage.

Therefore, the time to detect damage is delayed in the data analysis process and the accuracy of damage measurement is reduced

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