Marine Structures最新文献

{"title":"Further development of offshore floating solar and its design requirements","authors":"Arefeh Emami ,&nbsp;Madjid Karimirad","doi":"10.1016/j.marstruc.2024.103730","DOIUrl":"10.1016/j.marstruc.2024.103730","url":null,"abstract":"<div><div>Floating solar platform (FSP) installations in coastal waters provide a significant energy source for reaching the goal of global net-zero emissions by 2050. These alternative and beautiful green energy installations offer substantial renewable energy generation potential. However, developing robust design solutions is crucial for fully exploiting such potential in offshore environments. This review explores the fundamental requirements for designing FSPs in offshore settings from an engineering perspective. A primary focus is on the hydrodynamic and aerodynamic characteristics, stochastic behaviours, and nonlinear phenomena associated with these structures. Key design parameters such as geometry, modularity, connectivity, and mooring systems are subjected to comprehensive analysis. The interaction between wind, waves, and FSP dynamics is examined, with particular attention to wind-wave coupling. Additionally, complex nonlinear wave phenomena, such as slamming, overtopping, green water, sloshing, ringing, and springing, are thoroughly discussed. The review also highlights the application of previous fluid-structure interaction research in FSP design and development, addressing challenges and variations encountered in this field. Furthermore, the role of data-driven approaches, particularly machine learning, in enhancing the design and development of FSPs is illustrated. This comprehensive examination provides a more delicate understanding of the design challenges and requirements inherent in this rapidly evolving technological field.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"100 ","pages":"Article 103730"},"PeriodicalIF":4.0,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic analysis in polar exploration: Fluid-structure interaction modeling of projectile colliding with floating ice during water entry","authors":"Xinyu Hu,&nbsp;Yingjie Wei,&nbsp;Cong Wang","doi":"10.1016/j.marstruc.2024.103729","DOIUrl":"10.1016/j.marstruc.2024.103729","url":null,"abstract":"<div><div>In polar resource exploration, the interaction between polar detectors and floating ice, as well as their water entry mechanisms, are crucial for ensuring effective detector operation and data collection. This study developed a fluid-structure interaction (FSI) model to simulate the water entry of the projectile in a multidegree motion state upon collision with the floating ice, and the numerical method was validated through experiments. This study analyzes the mechanisms of cavity evolution and the laws of cavity pinch-off. This analysis further explores the motion states and dynamic characteristics under the interaction between the projectile and the floating ice. Additionally, this study also considers the influence of structural parameters of the floating ice, including thickness (<em>L_t</em>), width (<em>L_w</em>), and collision position (<em>S_d</em>), on the water entry process. The study reveals that increasing the submergence depth of the floating ice enhances the stability between the floating ice and water, and can mitigate flow separation phenomena generated by passive motion under inertial effects. Variations in the floating ice thickness significantly affect the cavity evolution and the projectile's underwater motion state. Conversely, variations in the floating ice width notably affect the liquid level disturbances, the development of splash crowns, and the evolution of passive water entry cavities. In specific multidegree motion states, various collision positions do not alter the evolution form of water entry cavities, yet the variation in collision positions notably affects floating ice displacement. As the collision position shifts from the center to the side edge of the floating ice, both the hydrodynamic forces on the projectile and the stress on the floating ice gradually decrease, with the decrease in hydrodynamic forces being the most significant, reaching up to 58%. This study is important for enhancing multi-body fluid-structure interaction algorithms and advancing polar exploration engineering development.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"100 ","pages":"Article 103729"},"PeriodicalIF":4.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic analysis of breaking wave impact on a floating offshore wind turbine via smoothed particle hydrodynamics","authors":"Shengzhe Wang ,&nbsp;Wei-Liang Chuang","doi":"10.1016/j.marstruc.2024.103731","DOIUrl":"10.1016/j.marstruc.2024.103731","url":null,"abstract":"<div><div>This work leverages Lagrangian smoothed particle hydrodynamics (SPH) to explore the structural and hydrodynamic response of floating offshore wind turbines (FOWT) subject to impulsive breaking waves. The SPH formulation was first validated against breaking wave impact on a model tension leg platform (TLP) which demonstrated good consistency with experimental results. Following validation, wave focusing was utilized to generate both breaking and nonbreaking extreme waves impacting a moored semi-submersible FOWT at full scale. Impulsive forces and accelerations resulting from the plunging breaker were observed to exceed that of nonbreaking waves by up to 70 % and 230 %, respectively, and were highly sensitive to the wave impingement location relative to the FOWT. However, wave breaking did not appear to significantly influence rigid body motions and yielded lower mooring tensions than its nonbreaking counterpart due to the short duration of impact. This work ultimately demonstrates the applicability of SPH for the simulation of breaking wave interactions with floating bodies and provides further impetus towards the study of FOWTs under such conditions.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"100 ","pages":"Article 103731"},"PeriodicalIF":4.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical investigation on the influence of bilge keel shape on roll damping","authors":"Hasan Islam Copuroglu ,&nbsp;Emre Pesman ,&nbsp;Toru Katayama","doi":"10.1016/j.marstruc.2024.103725","DOIUrl":"10.1016/j.marstruc.2024.103725","url":null,"abstract":"<div><div>Excessive roll amplitudes due to roll motion are undesirable in marine ships. Consequently, it is imperative to conduct a detailed analysis of roll motion and the associated roll damping characteristics. This study experimentally and numerically investigates the roll damping characteristics of bilge keels with various geometric shapes on a ship model under different roll amplitudes. By comparing the non-dimensional roll damping coefficients obtained from experiments and numerical analyses, it is observed that bilge keels with geometries differing from the conventional plate shape exhibit distinct roll damping coefficients. Specifically, bilge keels with sharper tip ends demonstrate higher roll damping coefficients. Based on these findings, it is recommended that the corners and tip end of bilge keels be sharpened to enhance the roll damping coefficient.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"100 ","pages":"Article 103725"},"PeriodicalIF":4.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a quick-connection device for installing pre-assembled offshore wind turbines","authors":"Behfar Ataei ,&nbsp;Zhengru Ren ,&nbsp;Karl Henning Halse","doi":"10.1016/j.marstruc.2024.103720","DOIUrl":"10.1016/j.marstruc.2024.103720","url":null,"abstract":"<div><div>Higher wind velocities and lower wind shear are two motivations driving the development of floating offshore wind turbines (OWTs). However, such designs suffer from high expenses and complicated installation scenarios. Installation of offshore wind turbines is challenging due to the unpredictable nature of the environment and the technical complexities, especially at offshore sites. Mating of OWT on top of the pre-installed substructure is one of the critical stages of the installation operation. Grouted, welded, and bolted connections are utilized conventionally, but all have shortcomings. Welded and grouted connections suffer from fatigue forces, while a bolted connection requires minimal installation tolerances and sensitivity to impact forces. The design of a quick connection device (QCD) is expected to reduce the installation time, expand the operational weather window, and overcome the limitations of the earlier connection devices.</div><div>The QCD described here comprises conic cross-sections, circular plates, and stiffeners connected to the floating substructure and OWT. This research uses a global model to estimate the relative velocities and displacements between the OWT and spar buoy. Furthermore, a local finite element model is developed to assess the influence of the impact forces and the design of the connection device. Implementing the hydrostatic stiffness of the floating spar within the impact simulations improved the simulation fidelity and reduced the impact damage. Different impact scenarios are performed, and the sensitivity of impact damage concerning the distribution of impact initiation points is assessed. Furthermore, an active control mechanism is used to reduce the relative motions between the installation vessel and the floating substructure. It is concluded that utilizing the anti-swing active control system minimizes the impact velocity and impact damage. This research can be extended by optimizing the design of the quick connection device.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"100 ","pages":"Article 103720"},"PeriodicalIF":4.0,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An ULS reliability-based design method for mooring lines using an efficient full long-term approach","authors":"Marina Leivas Simão ,&nbsp;Luis Volnei Sudati Sagrilo ,&nbsp;Paulo Maurício Videiro ,&nbsp;Mauro Costa de Oliveira","doi":"10.1016/j.marstruc.2024.103718","DOIUrl":"10.1016/j.marstruc.2024.103718","url":null,"abstract":"<div><div>In the long-term scenario, the environmental actions to which floating offshore structures are subjected to, such as waves, wind and current, are non-stationary stochastic processes. However, this long-term behavior is usually modeled as a series of short-term stationary conditions. In a full long-term analysis approach, an estimate of the N-year response can be obtained through a multi-dimensional integration over expected short-term environmental conditions. An innovative and more efficient long-term integration approach based on the Importance Sampling Monte Carlo Simulation (ISMCS) method is presented, where the uniform distribution over an environmental contour is used as the sampling function. In parallel, a multi-dimensional joint environmental model that statistically describes all relevant environmental parameters is employed, contemplating linear and directional variables, and thoroughly accounting for the occurrences of wind waves and swell. The methodology is applied to two FPSOs systems installed in Brazilian ultradeep waters. Ultimately, a design-oriented procedure based on the developed methodologies is provided, using an Ultimate Limit State (ULS) reliability-based design with calibrated safety factors in an LRFD (Load and Resistance Factors Design) format. It is shown that the developed procedures can be powerful tools to account for the simultaneous occurrence of wind sea and swell waves in offshore system response evaluations required in the design and life extension analyses.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"99 ","pages":"Article 103718"},"PeriodicalIF":4.0,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A probability-based study on failure mechanism and quantitative risk analysis for buried offshore pipelines subjected to third-party impact loads, exploring the effects of spatial variability of soil strength","authors":"Fengyuan Jiang ,&nbsp;Sheng Dong ,&nbsp;Carlos Guedes Soares","doi":"10.1016/j.marstruc.2024.103719","DOIUrl":"10.1016/j.marstruc.2024.103719","url":null,"abstract":"<div><div>Burial is an effective approach to offshore pipeline protection for impact loads. However, few studies address the influences of inherent soil spatial variabilities on failure behaviour of soil covers and pipelines, causing deviations. Therefore, a random field-large deformation finite element analysis framework is developed to explore the failure mechanisms of buried pipelines in spatially varying soils. The failure mode of soil cover is conformed to a local mode, where the failure path is insensitive to soil variability. The failure mechanism of pipelines depends on the competition mechanism between soil strengths and pipe-soil interactions, based on which two typical failure modes are summarized. Soil variability not only aggravates the impact damage but also stimulates the diversity of structural responses. Correlations between probabilistic damage degrees and multiple influential factors are discussed. Further, inspired by the principle of energy dissipation, an integrated quantitative risk assessment model is derived to reveal the failure risk evolution, where uncertainties from soil variabilities and structure-related factors are considered. The latter shows a significant influence, which may pose an additional failure probability of over 50 %. Different safety design approaches are compared, and spatial failure probability surfaces are configured for burial depth determination.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"99 ","pages":"Article 103719"},"PeriodicalIF":4.0,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elastic mode expansion in smoothed particle hydrodynamics framework for hydroelasticity and validation with 3D hydroelastic wedge impact experiments","authors":"Chaitanya Kesanapalli,&nbsp;HeonYong Kang","doi":"10.1016/j.marstruc.2024.103721","DOIUrl":"10.1016/j.marstruc.2024.103721","url":null,"abstract":"<div><div>To perform an efficient hydroelastic simulation with violent free surface interactions, we extend δ+ SPH to elastic modes of a floating structure through GPU parallelization, which includes the correction of velocity divergence with the deformation and computation of the structure's strain. Free surface interaction is supplemented with a segmented particle shifting and tensile instability correction. We validate the developed hydroelastic simulation for experiments of elastic wedge impacts with aluminum and composite panels. Through comparative analysis with different deadrise angles and impact velocities, we find that the improved free surface interactions reduce early separation from the deforming panels, leading to better prediction of the wedge acceleration and reasonably well-matched profiles of the free surface and panel deformation. The marginal difference is attributable to the water passing through the gaps of the physical test model built in three dimensions, which is absent in the simulation setup. Comparing strain time series, measured at two locations on the elastic panels, through three sets of simulations in different dimensions of the simulation set-up and mode shapes, we see that three-dimensional simulation with correct mode shapes in three dimensions accurately predicts the strain time series at both locations as well as the wedge acceleration. The hydroelastic simulation through the modal expansion in GPU parallelization can be utilized to efficiently predict various hydroelastic phenomena with violent free surface interactions.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"99 ","pages":"Article 103721"},"PeriodicalIF":4.0,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extreme nonlinear ship response estimations by active learning reliability method and dimensionality reduction for ocean wave","authors":"Tomoki Takami ,&nbsp;Masaru Kitahara ,&nbsp;Jørgen Juncher Jensen ,&nbsp;Sadaoki Matsui","doi":"10.1016/j.marstruc.2024.103723","DOIUrl":"10.1016/j.marstruc.2024.103723","url":null,"abstract":"<div><div>An efficient extreme ship response prediction approach in a given short-term sea state is devised in the paper. The present approach employs an active learning reliability method, named as the active learning Kriging + Markov Chain Monte Carlo (AK-MCMC), to predict the exceedance probability of extreme ship response. Apart from that, the Karhunen-Loève (KL) expansion of stochastic ocean wave is adopted to reduce the number of stochastic variables and to expedite the AK-MCMC computations. Weakly and strongly nonlinear vertical bending moments (VBMs) in a container ship, where the former only accounts for the nonlinearities in the hydrostatic and Froude-Krylov forces, while the latter also accounts for the nonlinearities in the radiation and diffraction forces together with slamming and hydroelastic effects, are studied to demonstrate the efficiency and accuracy of the present approach. The nonlinear strip theory is used for time domain VBM computations. Validation and comparison against the crude Monte Carlo Simulation (MCS) and the First Order Reliability Method (FORM) are made. The present approach demonstrates superior efficiency and accuracy compared to FORM. Moreover, methods for estimating the Mean-out-crossing rate of VBM based on reliability indices derived from the present approach are proposed and are validated against long-time numerical simulations.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"99 ","pages":"Article 103723"},"PeriodicalIF":4.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural performance at the joint of precast pile-supported pier structure","authors":"Sang Kyu Cho ,&nbsp;Tae Hoon Koo ,&nbsp;Won Chul Cho","doi":"10.1016/j.marstruc.2024.103722","DOIUrl":"10.1016/j.marstruc.2024.103722","url":null,"abstract":"<div><div>Recently, precast construction methods have been increasingly applied to pile-supported pier structures in coastal areas, offering simplified construction processes, shorter construction periods, and minimized environmental pollution. The use of precast members in offshore construction allows for prefabricated assembly, reducing the need for temporary installations and minimizing field casting work. However, pile-supported pier structures in coastal regions are subject to various marine loads, such as wave, berthing, wind forces and live load, along with uplifting forces due to sea-level rise, making it essential to verify the joints—typically the most vulnerable part of precast structures. This study conducts numerical analyses and experimental tests to evaluate the behavior of joints in newly developed precast structures and assess their structural safety. Results indicate that the failure mode of the structure initiates and progresses at the joint where the precast members connect to field-cast sections. Additionally, it was confirmed that failure originates at the weakest point in areas where precast girders, precast pile caps, and piles are interconnected. Nonetheless, the proposed structure demonstrated structural performance that significantly exceeded the design load.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"99 ","pages":"Article 103722"},"PeriodicalIF":4.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}