Ice model for structural integrity In below zero environments, ice poses a significant concern for structures as its bearing load and impact can threaten their integrity. Understanding how structures perform against ice-loads in therefore vital to ensure that structures continue to operate safely. Climate Change and Environment Structures, such wind turbines are precisely engineered mechanisms, and as such, icy loads may alter or impede their operations. Offshore oilrigs are designed to withstand enormous tidal and wind forces, but ice may complicate matters enormously. Therefore, suitable models for testing need to be developed that will provide accurate data on ice flows and dynamics. Under the STRICE project, funded by the EC's EESD programme, such a model was developed. The intended objective was to assess the interaction of ice on offshore structures especially considering that ice flows can have an impact velocity of a meter per second. This, along with their weight can pose considerable threats to structures and therefore the project's secondary aim was to increase both quality and quantity of data. During the three years in which the project ran, data was collected on time series of ice loads, ice thickness, acceleration and inclination, ice-structure interaction, amongst others. Additional environmental data and ice maps helped compile statistical analysis. These were coupled with data such as ice-compression, compressive strength, stress-strain curves and elastic modulus versus stress levels and a comprehensive modelling tool was compiled. The modelling tool does not consider non-linear effects of ice-structure interactions; and this imparts two limitations. First, self-excited vibrations are not incorporated and secondly, the model considers only those structures that are relatively stiff and the waterline. However, the model is still highly usable for the design of limited states posed by fatigue, serviceability and strength of the structure. Further research is needed, to complement that data.
