Irregular, unidirectional surface water waves incident on model ice in an ice tank are used as a physical model of ocean surface wave interactions with sea ice. Results are given for an experiment consisting of three tests, starting with a continuous ice cover and in which the incident wave steepness increases between tests. The incident waves range from causing no breakup of the ice cover to breakup of the full length of ice cover. Temporal evolution of the ice edge, breaking front and mean floe sizes are reported. Floe size distributions in the different tests are analysed. The evolution of the wave spectrum with distance into the ice-covered water is analysed in terms of changes of energy content, mean wave period and spectral bandwidth relative to their incident counterparts, and pronounced differences are found between the tests. Further, an empirical attenuation coefficient is derived from the measurements and shown to have a power-law dependence on frequency comparable to that found in field measurements. Links between wave properties and ice breakup are discussed.

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The environment in cold regions undergoes significant changes that manifest in rising temperatures and melting ice caps. These processes allow access to new areas for shipping and the installation of structures. However, the occurring changes are not solely a reduction of ice, but also waves increasingly occur in cold regions contributing to ice break up in the Marginal Ice Zone (MIZ) and the transport of ice towards the open sea. Much work has been done to combine the single topic disciplines: wave-hydrodynamics, ice mechanics and structure mechanics to wave-structure (WSI) and ice-structure interaction (ISI). The changing environment in cold regions and the increased wave activity form a new combined discipline: wave-ice-structure interaction (WISI). This paper addresses existing knowledge gaps of the future loading scenario WISI that need to be addressed in engineering to ensure safety for future operations in Polar Regions. The knowledge gaps however, do not only refer to the discipline interfaces, i.e. challenges in combining them, but also to knowledge gaps within them. Wave statistics and the cross-effect between wave and ice are widely unknown which limits the definition of a design wave-scenario. Structures in such environments are exposed to subzero temperatures and neither their impact on properties nor on fatigue life is fully understood. While most phenomena of these two disciplines and their implementation into numerical models are established the ice mechanics appear as the weakest link. Ice is a complex material and not all aspects of its mechanical behaviour are understood and if – the implementation into (numerical) models has not been successful yet. Ice pieces that are energetically charged by waves and collide with structures at high velocities and for such high impact loads the governing ice mechanics are hardly covered by the state of the art or not at all.

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Performance simulation tools are of high significance for the design and especially the optimization of ships and offshore structures. However, for ice covered waters such tools are hardly available and are either costly as ice model tests or have a limited range of validity, such as semi-empirical formulas. This arises from the complexity of ice as material and insufficient knowledge on its mechanics. This paper presents a numerical analysis for model-scale ice in which material parameters are developed that can represent: tension, compression and in-situ downward bending. Those parameters are incorporated into a material model following the Lemaitre damage law. The developed material characteristics for model-scale ice are intended to support the design process of ships and offshore structures. The key phenomenon joining the deformation processes in bending together with those in compression and tension, proved to be the through thickness dependency of properties. This analysis and development is a continuation of previously presented parameters for compression and tension and is developed in agreement with experimental evidence.

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