Structural Condition Identification for Free Spanning Submarine Pipelines

摘要

The operational performance of the free spanning submarine pipeline is closely related to the structural condition. However, due to the underwater environment and condition evolution, it is very difficult to exactly obtain the information about the structural condition of the free spanning submarine pipeline. In this paper, we propose a novel methodology to identify the structural condition with the vibration responses of the free spanning submarine pipelines. Firstly, the nonlinear kernel discirminant analysis (KDA) was adopted to identify the structural condition of the free spanning submarine pipelines. Secondly, the condition-sensitive features, such as natural frequencies, normalized frequencies and frequency change ratios, were proposed in the study. Finally, the feasibility and effectiveness of the proposed approach was numerically studied. The analytical results demonstrate that the proposed approach can identify effectively each condition of free span for on-line monitoring of the submarine pipelines.