Article
Energy & Fuels
E. Faraggiana, M. Sirigu, A. Ghigo, G. Bracco, G. Mattiazzo
Summary: This paper proposes an efficient optimization tool for optimizing the main geometry design parameters of floating wind turbines. By using a genetic algorithm and Kriging surrogate model, the structural cost of the buoy is reduced by two to three times the worst configuration, with a 25% cost reduction between the most and the least restrictive optimal cases.
Article
Green & Sustainable Science & Technology
Daniel Micallef, Abdolrahim Rezaeiha
Summary: Over the past decade, there has been a steady increase in scientific articles on rotor aerodynamics of offshore wind turbines, highlighting the critical role of aerodynamics in overcoming specific barriers in multi-physics systems. Current trends in research focus on the interaction between aerodynamics and other fields, such as platform hydrodynamics and control, with common approaches being coupled or uncoupled studies. The literature mainly addresses isolated floating turbines, while studies on interactions between floating turbines are limited.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Review
Engineering, Marine
Tiago Fazeres-Ferradosa, Joao Chambel, Francisco Taveira-Pinto, Paulo Rosa-Santos, Francisco V. C. Taveira-Pinto, Gianmaria Giannini, Piet Haerens
Summary: Offshore wind is currently the most developed sector of marine renewable energy commercially. The optimization of offshore wind foundations, particularly in terms of scour protections, is crucial for further competitiveness. This paper offers an overview of recent improvements and challenges in scour protections for offshore wind turbines, highlighting the importance of ongoing research in this field.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Navid Majdi Nasab, Jeff Kilby, Leila Bakhtiaryfard
Summary: This paper determines the optimal dimensions of monopiles to support the integrated assembly through finite element analysis and macro-element model, providing technical support for the integration of offshore wind and tidal energy.
Article
Environmental Sciences
Nils Christiansen, Jeffrey R. R. Carpenter, Ute Daewel, Nobuhiro Suzuki, Corinna Schrum
Summary: This study investigates the structure drag and physical impacts of offshore wind turbines on the marine environment of the German Bight. Two modeling approaches for simulating wind turbine foundation effects are presented, and the use of very high resolution in hydrostatic modeling is discussed. The study demonstrates the impacts of monopile drag on hydrodynamic conditions using a low-resolution structure drag parameterization, validated against in-situ measurements. The simulations show that structure-induced mixing affects regional scales due to additional turbulence production, leading to changes in current velocities and stratification.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Engineering, Marine
Kerman Vazquez, Raul Ruben Rodriguez, M. Dolores Esteban
Summary: This article investigates the corrosion of reinforcement in concrete structures in offshore wind farms and develops a tool to predict the diameter loss. The results indicate that the proposed combination model provides accurate prediction results. This is a valuable tool for operators of offshore wind farms.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Review
Green & Sustainable Science & Technology
L. Wang, A. Kolios, X. Liu, D. Venetsanos, C. Rui
Summary: This paper presents a state-of-the-art reliability assessment of offshore wind turbine (OWT) support structures, highlighting the importance of considering uncertainties in soil properties and environmental loads. It provides a comprehensive review on structural reliability, reliability-based calibration of codes, fatigue reliability, and the implementation of reliability assessment. The paper also discusses current and future developments in reliability assessment, such as reliability-based design optimization, multi-hazard reliability analysis, and risk-based inspection.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Article
Engineering, Marine
K. Vazquez, R. R. Rodriguez, M. D. Esteban
Summary: In order to ensure the sustainable development of offshore wind farms, this article proposes an inventory proposal for gravity-based support structures (GBS). By analyzing data from 17 wind farms, the article presents a comprehensive inventory proposal for GBS foundations, which demonstrates its applicability and functionality through testing.
Article
Environmental Studies
Maria Clara Iruzun Martins, Matt I. D. Carter, Sally Rouse, Debbie J. F. Russell
Summary: Offshore man-made structures (MMS), such as O&G platforms and wind turbines, have the potential to influence ecosystem dynamics. However, there is a lack of comprehensive and up-to-date MMS database, hindering effective policy decisions and scientific assessments.
Article
Construction & Building Technology
Wout Weijtjens, Andre Stang, Christof Devriendt, Peter Schaumann
Summary: This paper investigates the fatigue-driven design of offshore wind turbines, focusing on the impacts of cyclic shell forces and bolt tension forces on bolted ring flanges. Analysis of monitoring data from three wind turbines revealed load transfer coefficients favorable for fatigue life, confirming the accuracy of the FE model.
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH
(2021)
Article
Green & Sustainable Science & Technology
He Li, H. Diaz, C. Guedes Soares
Summary: This study extends the conventional failure mode and effect analysis methodology by introducing weights for severity, occurrence, and detection to analyze failures in the support structure of a floating offshore wind turbine. Recommendations for corrections and preventive actions are suggested based on the analysis. The proposed technique is validated through a comparison study, showing that it is more in line with practical use and offers flexibility.
Review
Engineering, Marine
Baran Yeter, Yordan Garbatov
Summary: This study provides a review of the structural integrity of fixed support structures for offshore wind turbines. It covers the history of fatigue and fracture phenomena, modelling techniques, crack estimation methods, and life prediction models. The study also reviews influential research on structural integrity and reliability, and discusses a risk-based assessment framework.
Article
Green & Sustainable Science & Technology
Yangtian Yan, Yang Yang, Musa Bashir, Chun Li, Jin Wang
Summary: This paper investigates the structural dynamics of 10 MW offshore wind turbines supported by different substructures under various loadings. It reveals that the tripod and jacket have good stability but a higher risk of local failure under earthquakes. The study also suggests that the stiffness of the substructures can improve the stability of the jacket and tripod.
Article
Environmental Sciences
Maryam Golbazi, Cristina L. Archer, Stefano Alessandrini
Summary: This study used high-resolution numerical simulations to investigate the surface meteorological impacts of large offshore wind farms equipped with extreme-scale wind turbines. The results showed that the impacts are statistically significant but negligible in magnitude.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Review
Engineering, Marine
Mengmeng Wang, Chengye Wang, Anna Hnydiuk-Stefan, Shizhe Feng, Incecik Atilla, Zhixiong Li
Summary: Global wind energy has developed rapidly in recent years, with offshore wind turbines being applied to various applications. Strengthening structural reliability is crucial due to the vulnerability of OWT support structures, and real-time monitoring and digital twin technology can reduce operation costs and prolong the wind turbine service life.
Article
Construction & Building Technology
Max Herbers, Marc Wenner, Steffen Marx
Summary: This study compares the predicted values from different material models with monitoring data to assess their accuracy. The results show that the material models according to Eurocode 2 provide a better prediction of deformations in large viaducts when compared to the fib Model Code 2010.
STRUCTURAL CONCRETE
(2023)
Article
Engineering, Mechanical
Henrik Becks, Abedulgader Baktheer, Steffen Marx, Martin Classen, Josef Hegger, Rostislav Chudoba
Summary: Research on fatigue in concrete has been ongoing for many years, but there are still many unanswered questions. The process of fatigue-induced damage evolution and stress redistribution in concrete structures is not fully understood. Experimental studies in this area have been limited to a few cases involving nonuniform stress profiles. To investigate the influence of such stress configurations on material and structural degradation, researchers have developed a measuring concept combining various measurement techniques. The experiments conducted using this concept provide visualizations of the propagating fatigue degradation in concrete beams under fatigue loading, which can significantly contribute to the validation of design rules and material models for concrete fatigue.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Civil
Fabian Klein, Steffen Marx
Summary: This article investigates the influence of adjacent segments on the torsional load bearing behavior of assembled half-shell towers for wind energy turbines. Numerical comparative studies show that an adjacent half-shell pair level at the top and bottom is sufficient to take the influence of the entire tower structure into account.
ENGINEERING STRUCTURES
(2023)
Article
Construction & Building Technology
Max Herbers, Bertram Richter, Daniel Gebauer, Martin Classen, Steffen Marx
Summary: Experimental investigations were conducted to test the suitability of different types of distributed fiber optic sensors (DFOS) for crack monitoring. Clear differences were observed in the strain curves and crack widths measured by different DFOS types. Two robust DFOS, which can be used on construction sites, were focused on and compared to a layered sensing cable. The strain distribution and crack widths obtained by integrating the strain curves showed good agreement with digital image correlation (DIC) measurements.
STRUCTURAL CONCRETE
(2023)
Article
Chemistry, Multidisciplinary
Enrico Baumgaertel, Steffen Marx
Summary: Carbon fiber reinforced plastics are being used more frequently across all industries, leading to an increase in the production of new carbon fibers and a larger number of end-of-life components. Currently, these components can only be partially reused, resulting in a suboptimal closed-material cycle. This article discusses the recycling and further processing of carbon components, as well as the reuse of recycled carbon fibers in reinforcement elements. The reuse of carbon fibers in the construction sector has the potential to effectively close the carbon cycle and reduce concrete consumption.
APPLIED SCIENCES-BASEL
(2023)
Article
Multidisciplinary Sciences
Daniel Gebauer, Raul Enrique Beltran Gutierrez, Steffen Marx, Marko Butler, Konrad Grahl, Thomas Thiel, Stefan Maack, Stefan Kuettenbaum, Stephan Pirskawetz, Wolfgang Breit, Martin Schickert, Marco Krueger
Summary: Two test series were examined using nondestructive measuring methods to determine their compressive strength. The two methods used were rebound hammer and ultrasonic pulse velocity measurement. Two types of geometries, drilled cores and cubes, were investigated.
Article
Construction & Building Technology
Jiafeng Zhou, Chongjie Kang, Mengyan Peng, Marina Stuempel, Steffen Marx
Summary: This study examines the bond behaviors between concrete and glass fiber reinforced polymer (GFRP)/stainless steel bars using distributed fiber optical sensors (DFOSs). Tension and bond behaviors are investigated through testing, with a focus on a type of GFRP bars with a grey coating. The study also compares the results obtained from DFOS in the bar groove and DFOS on the bar surface, and evaluates the impact of different DFOS coatings and adhesives on measured bar strains.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Frank Liebold, Franz Wagner, Josiane Giese, Szymon Grzesiak, Christoph de Sousa, Birgit Beckmann, Matthias Pahn, Steffen Marx, Manfred Curbach, Hans-Gerd Maas
Summary: This study investigates the behavior of carbon-reinforced concrete (CRC) through three-point bending tests and large-scale in situ computed tomography (CT). The focus is on crack width and quality control of large CRC beams using new experimental setups and analysis methods. The results are crucial for the safe and effective application of CRC and quality control measures.
Article
Construction & Building Technology
Josiane Giese, Birgit Beckmann, Frank Schladitz, Steffen Marx, Manfred Curbach
Summary: This study focuses on the structural behavior of slender carbon-reinforced concrete structures under axial compression, and quantifies the influence of slenderness ratio and load eccentricity. The results show that the failure stresses of samples with high slenderness ratios can be successfully predicted, while the specimens with intermediate to low slenderness ratios should consider plastic buckling phenomenon.
Article
Construction & Building Technology
Peter Betz, Verena Curosu, Stefan Loehnert, Steffen Marx, Manfred Curbach
Summary: This study investigates the multiaxial performance of fine-grained concrete and compares it with high-strength concrete with normal aggregate. It is found that by using existing data and appropriate material models, it is possible to accurately characterize and numerically simulate fine-grained concrete.
Article
Construction & Building Technology
Michael Frenzel, Enrico Baumgaertel, Steffen Marx, Manfred Curbach
Summary: This article presents the cracking and load-bearing behavior of carbon-reinforced prismatic concrete tensile specimens. Different carbon reinforcement grids with varying geometries and impregnations were used, and the reinforcement surfaces were partially coated with fine sand to enhance the bond with the concrete. The article discusses the influence of different parameters on crack development, including crack width and spacing.
Article
Construction & Building Technology
Josiane Giese, Max Herbers, Frank Liebold, Franz Wagner, Szymon Grzesiak, Christoph de Sousa, Matthias Pahn, Hans-Gerd Maas, Steffen Marx, Manfred Curbach, Birgit Beckmann
Summary: The study focuses on the crack pattern of reinforced concrete and explores the possibility of using X-ray computed tomography to analyze the internal mechanics. Through CT tests on carbon-reinforced concrete beams under bending load, the evolution of cracks at different stages of their formation was analyzed.
Article
Materials Science, Characterization & Testing
Ronghua Xu, Raul Enrique Beltran-Gutierrez, Max Kaeding, Alexander Lange, Steffen Marx, Joern Ostermann
Summary: This study compares the signal response of four different couplant materials in acoustic emission analysis and ultrasonic testing, and analyzes their impact on the signal response of a piezoelectric sensor. The results indicate that acrylic adhesive pads and hot glue demonstrate more reliable signal transmission in certain frequency ranges, while honey and vaseline perform better in other frequency ranges. Acrylic adhesive pads and honey are considered the preferred couplant materials.
NDT & E INTERNATIONAL
(2024)
Article
Construction & Building Technology
Bertram Richter, Max Herbers, Steffen Marx
Summary: Distributed fiber optic sensing is a promising technology for structural health monitoring, allowing for continuous and high-resolution strain measurements. Different approaches for crack width calculation exist depending on the application of the sensor. Scalable and automated analysis methods are needed to handle the large amount of data and derive useful information from measurements.
STRUCTURAL CONCRETE
(2023)
Proceedings Paper
Engineering, Civil
Alexander Lange, Max Kaeding, Reemt Hinrichs, Joern Ostermann, Steffen Marx
Summary: Aging infrastructure, especially bridges, has become a serious issue in industrialized countries. Detecting wire break events in bridge tendons is important for ensuring structural integrity and safety. Recent research suggests the use of acoustic emissions (AE) using ultrasonic sensors for this purpose, and experiments have shown promising results in detecting wire breaks over long distances.
EUROPEAN WORKSHOP ON STRUCTURAL HEALTH MONITORING (EWSHM 2022), VOL 3
(2023)