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Hammer, T.C. (author), Puolakka, Otto (author), Hendrikse, H. (author)
A modeling approach to simulate ice-induced vibrations of vertically sided offshore structures in ice tank experiments is presented. The technique combines replica modeling with the preservation of kinematics during ice-structure interaction. The technique was chosen based on the theoretical understanding that ice-induced vibrations are...
journal article 2024
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Høyland, Knut V. (author), Nord, Torodd S. (author), Hendrikse, H. (author), Tuhkuri, Jukka (author), Polojärvi, A.S. (author), von Bock und Polach, Franz (author), Heinonen, Jaakko (author), Eik, Kenneth Johannessen (author), Teigen, Sigurd Henrik (author)
EU urgently needs to increase the development of secure and green energy, and this includes renewables such as Offshore wind energy. An expansion of Offshore wind will include the Baltic where sea ice is one of the major uncertainties. To ensure that the wind turbines are safe for people and the environment, while keeping them economically...
conference paper 2023
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Peel, Grant J (author), Gedikli, Ersegun D (author), Hendrikse, H. (author)
Climate change is affecting global weather patterns, but nowhere is this more apparent than in the Arctic. The Arctic is an extreme environment going through rapid climate change, resulting in the opening of new shipping lanes and leading to less multiyear ice formation. This increases the risk of collision with the sea ice making it difficult...
conference paper 2023
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Hendrikse, H. (author), Owen, C.C. (author)
For offshore wind turbines on monopile or jacket foundations without ice cones, one of the relevant design load cases is that of ice floes or level ice crushing against the structure resulting in ice-induced vibrations. In relation to that design load case, a relevant question is which ice strength coefficient to use in the crushing formula in...
conference paper 2023
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Høyland, Knut V. (author), Nord, Torodd S. (author), Hendrikse, H. (author), Tuhkuri, Jukka (author), Polojärvi, Arttu (author), von Bock und Polach, Franz (author), Heinonen, Jaakko (author), Johannessen Eik, Kenneth (author), Teigen, Sigurd Henrik (author)
EU urgently needs to increase the development of secure and green energy, and this includes renewables such as Offshore wind energy. An expansion of Offshore wind will include the Baltic where sea ice is one of the major uncertainties. To ensure that the w ind turbines are safe for people and the environment, while keeping them economically...
conference paper 2023
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van der Stap, Florian L. (author), Nielsen, Martin B. (author), Owen, C.C. (author), van der Male, P. (author), Hendrikse, H. (author)
For the design of offshore foundations in regions such as the Baltic Sea, it is paramount that ice-structure interaction is appropriately considered. For the monopile, a common foundation for offshore wind turbines, challenges with ice-induced vibrations and high ridge loads may require ice-mitigating measures to be included in the design. A ...
conference paper 2023
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Petry, Alice (author), Hammer, T.C. (author), Polojärvi, Arttu (author), Hendrikse, H. (author), Puolakka, Otto (author)
Increased activity in planning offshore wind farms in the northern Baltic Sea has renewed interest in studying the effect of ice cones on ice failure mechanisms. In preparation for future experiments with steep ice cones, preliminary ice basin experiments were performed at the Aalto Ice and Wave Tank to investigate how model ice fails against a...
conference paper 2023
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Hammer, T.C. (author), Hendrikse, H. (author)
Drifting sea ice failing in crushing against vertically-sided offshore structures can cause ice-induced vibrations. Offshore structures are typically founded on slender structures to minimize the load effect of waves and currents. In combination with large top masses, those offshore structures often provide sufficient compliance for ice-induced...
conference paper 2023
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Hendrikse, Hans C. (author), El Khallabi, Hamza (author), Hartog, Thomas (author), Varveri, Aikaterini (author), Tolboom, Anthon (author)
The concept of a circular economy, where waste materials are transformed into valuable resources, is gaining increasing attention. However, many waste streams are difficult to recycle due to their mixed composition and broad molecular distribution. This paper explores the potential of repurposing mixed materials, specifically focusing on...
journal article 2023
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Hammer, T.C. (author), Willems, Tom (author), Hendrikse, H. (author)
For offshore wind farms which are planned in sub-arctic regions like the Baltic Sea and Bohai Bay, support structure design has to account for load effects from dynamic ice-structure interaction. There is relatively high uncertainty related to dynamic ice loads as little to no load- and response data of offshore wind turbines exposed to...
journal article 2023
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Owen, C.C. (author), Hendrikse, H. (author)
The manual application of universal (Rigsby) stage techniques is commonly used to determine the fabric of thin sections of ice viewed with crossed-polarized light. This process can require hours of focus in cold conditions to identify the c-axis of each grain in a thin section. Automated ice texture and fabric methods of several forms exist...
journal article 2023
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Owen, C.C. (author), Hammer, T.C. (author), Hendrikse, H. (author)
Cyclic crushing experiments with a haversine velocity waveform were performed on passively confined, freshwater columnar ice specimens for a variety of velocities and frequencies. The aim of the experiments was to study the ice deformation and failure behavior in crushing when loaded at a predefined displacement pattern closely resembling the...
journal article 2023
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Owen, C.C. (author), Hammer, T.C. (author), Hendrikse, H. (author)
A series of ice penetration tests with a rigid structure, with controlled oscillation, and with a single-degree-of-freedom structure were performed to investigate the peak load-velocity dependence for ethanol-doped model ice during a test campaign at the Aalto Ice and Wave Tank. For the rigid structure and controlled-oscillation tests, the...
journal article 2023
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Hammer, T.C. (author), Hendrikse, H. (author)
The effect of misalignment between wind- and ice loading direction on the development of ice-induced vibrations of offshore wind turbines has been investigated experimentally. In the experiments a hybrid test setup was used to study the structural response to combined loading from physical model ice and numerically applied wind. The...
journal article 2023
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Hendrikse, H. (author), Hammer, T.C. (author), van den Berg, M.A. (author), Willems, Tom (author), Owen, C.C. (author), van Beek, C. (author), Ebben, Nick J.J. (author), Puolakka, Otto (author), Polojärvi, Arttu (author)
Basin tests were performed at the Aalto Ice Tank to gather data on ice-structure action and interaction from ice failing against a vertically sided cylindrical pile. The tests were performed with a real-time hybrid test setup, which combined physical and numerical components to simulate a range of test structures in real-time. The dataset...
journal article 2022
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van den Berg, M.A. (author), Owen, C.C. (author), Hendrikse, H. (author)
This study analyses the results from basin tests with a vertically sided cylindrical pile loaded by ice failing in crushing. Tests were performed with a ‘rigid’ structure and with structural models representing a series of single-degree-of-freedom (SDOF) oscillators covering a wide range of mass, frequency, and damping values. The structural...
journal article 2022
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Hendrikse, H. (author), Hammer, T.C. (author), Owen, C.C. (author), van den Berg, M.A. (author), van Beek, C. (author), Polojärvi, Arttu (author), Puolakka, Otto (author), Willems, Tom (author)
With the recent surge in development of offshore wind in the Baltic Sea, Bohai Sea and other ice-prone regions, a need has arisen for new basin tests to qualify the interaction between offshore wind turbines and sea ice. To this end, a series of model tests was performed at the Aalto ice basin as part of the SHIVER project. The tests were aimed...
conference paper 2022
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Braun, Moritz (author), Dörner, Alfons (author), Willems, Tom (author), Seidel, Marc (author), Hendrikse, H. (author), Høyland, Knut V. (author), Fischer, Claas (author), Ehlers, Sören (author)
Fixed offshore wind turbines are increasingly developed for high latitude areas where not only wind and wave loads need to be considered, but also moving sea ice. Current structural design rules do not adequately consider the effect of ice loading on fatigue life, due to missing studies on fatigue strength of welded joints under combined wind,...
conference paper 2022
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Hornnes, Vegard (author), Hammer, T.C. (author), Høyland, Knut V. (author), Hendrikse, H. (author), Turner, Joshua (author)
In bodies of water where ice is not an annual occurrence, such as in the Southern Baltic Sea, the design of offshore wind turbines is complicated by the difficulty involved in estimating the relevant ice parameters (thickness, velocity, and strength) and their corresponding probabilities of occurrence (return periods). In this paper, the use of...
conference paper 2022
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Owen, C.C. (author), Hammer, T.C. (author), Hendrikse, H. (author)
For the topic of predicting ice-induced vibrations of vertically sided offshore structures, the rate-dependent ductile-to-brittle transitional deformation and failure behavior of ice is critical but remains superficially understood. To investigate this knowledge gap, a test setup has been designed which allows for in-situ crossed-polarization...
conference paper 2022
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