A Delay Vector Variance based Marker for an Output-Only Assessment of Structural Changes in Tension Leg Platforms

11th International Conference on Damage Assessment of Structures

物理学;材料科学

Jaksic, V.^1,2 ; Wright, C.^1 ; Mandic, D.P.^3 ; Murphy, J.^1 ; Pakrashi, V.^1,2

Beaufort, Environmental Research Institute, University College Cork, Cork, Ireland^1

Dynamical Systems and Risk Laboratory, School of Engineering, University College Cork, College Road, Cork, Ireland^2

Department of Electrical and Electronic Engineering, Imperial College London, London

SW7 2BT, United Kingdom^3

关键词: Delay vector variances;    Exposure conditions;    ON dynamics;    Output signal;    Structural condition;    Time-series data;    Wave conditions;    Wave loadings;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/628/1/012059/pdf
DOI  :  10.1088/1742-6596/628/1/012059

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Although aspects of power generation of many offshore renewable devices are well understood, their dynamic responses under high wind and wave conditions are still to be investigated to a great detail. Output only statistical markers are important for these offshore devices, since access to the device is limited and information about the exposure conditions and the true behaviour of the devices are generally partial, limited, and vague or even absent. The markers can summarise and characterise the behaviour of these devices from their dynamic response available as time series data. The behaviour may be linear or nonlinear and consequently a marker that can track the changes in structural situations can be quite important. These markers can then be helpful in assessing the current condition of the structure and can indicate possible intervention, monitoring or assessment. This paper considers a Delay Vector Variance based marker for changes in a tension leg platform tested in an ocean wave basin for structural changes brought about by single column dampers. The approach is based on dynamic outputs of the device alone and is based on the estimation of the nonlinearity of the output signal. The advantages of the selected marker and its response with changing structural properties are discussed. The marker is observed to be important for monitoring the as- deployed structural condition and is sensitive to changes in such conditions. Influence of exposure conditions of wave loading is also discussed in this study based only on experimental data.