Offshore Floating Structures (OFSs) present a major category of offshore structures that are often subjected to severe environmental conditions and harsh critical loading scenarios. The state of an OFS during its life-cycle must remain in the domain specified in the design, although this can be altered by normal aging due to usage, the action of the environment and accidental events. In recent years, the field of Structural Health Monitoring (SHM) has been growing at a fast rate, especially in different applications within the offshore structures' field (e.g. platforms and systems in oil and gas technology, risers, and offshore wind technology). Based on the monitored data of the SHM a diagnosis and most importantly a prognosis of the health status of the OFS can be assessed. Usually, measured data in long time span of different structural response quantities are used for the aforementioned assessment with, in some cases, unmeasured data. This paper deals with two objectives for the case of monitored structural response data of an OFS:
the implementation of clustering techniques for analysis of the structural response data and
the completion of missing structural response data based on appropriate clustering techniques.
A big number of offshore structures are in operation in the different related ocean technologies that exist, namely, oil and gas, renewable energy, coastal, fishery and transportation. It is estimated that more than 10,000 offshore structures of different types, floating or fixed, have been installed and are in operation worldwide (Chakrabarti, 2005). The aforementioned number of offshore structures is expected to increase the coming years. Offshore structures are placed in the ocean environment, where particular conditions exist with harsh induced loadings (Hirdaris et al., 2014). The long term exposure of the offshore structures to these conditions (e.g. severe wave and wind conditions, water pressure actions, vortex shedding, salinity, accidental events, etc.) will affect their design and service life, while anomalies, degradation and damages may incur as a result. Damages in offshore structures may have catastrophic effects in different aspects.
