Damage identification of platform structure based on cross correlation function and PCA in random ocean environment
LI Wei1,2, HUANG Yan1,3
1. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300350, China;
2. School of Civil Engineering, Tianjin University, Tianjin 300350, China;
3. Tianjin Key Laboratory of Port and Ocean Engineering, Tianjin University, Tianjin 300350, China
Abstract：In order to ensure safety of offshore platform, identify and locate its damage in time, the structural health monitoring technology of offshore platform has become an important issue for scholars. Here, for a jacket platform in service, its dynamic responses under different random wave excitations were numerically simulated in health state and damage state, respectively. In the process of damage identification, cross-correlation analyses of dynamic responses of different positions of the platform were performed to extract damage sensitive features. Then the principal component analysis (PCA) method was used to extract principal component from complex data. Finally, the damage index was defined and the damage identification was done. Aiming at the problem of the traditional PCA method’s accuracy for damage identification of some members being not high, a new method of selecting principal components was proposed to improve the traditional PCA method. The results showed that the improved PCA method can effectively improve the accuracy of damage identification to correctly identify structural damage under random wave condition.
李伟1,2，黄焱1,3. 随机海洋环境下基于互相关函数和主成分分析的平台结构损伤辨识[J]. 振动与冲击, 2021, 40(7): 179-187.
LI Wei1,2, HUANG Yan1,3. Damage identification of platform structure based on cross correlation function and PCA in random ocean environment. JOURNAL OF VIBRATION AND SHOCK, 2021, 40(7): 179-187.
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