Marine Structures最新文献

{"title":"Isogeometric contact analysis in subsea umbilical and power cables","authors":"Tianjiao Dai ,&nbsp;Shuo Yang ,&nbsp;Xing Jin ,&nbsp;Svein Sævik ,&nbsp;Jiaxuan Zhang ,&nbsp;Jun Wu ,&nbsp;Naiquan Ye","doi":"10.1016/j.marstruc.2025.103960","DOIUrl":"10.1016/j.marstruc.2025.103960","url":null,"abstract":"<div><div>Subsea umbilical and power cables contain a large number of contact interfaces between different geometries and materials. These complex interactions rise significant challenges for accurately considering contact surface properties by using traditional analytical solutions or finite element methods. These properties have been identified as the most sensitive parameters when performing the numerical simulation for stress analysis. Therefore, it is essential to apply a novel approach for contact analysis which improves the accuracy and efficiency for predicting contact properties. This paper presents an isogeometric analysis (IGA) approach addressing contact problems in dynamic umbilicals and power cables. Firstly, this isogeometric contact algorithm is formulated in MATLAB as a tool including the geometry description, contact detection and penalty function. Secondly, the contact interface between a steel tube and an outer sheath in an dynamic umbilical is established by this IGA contact algorithm and validated against that in ABAQUS for proving the accuracy and efficiency of IGA. Finally, the effects of element refinement, geometrical description, penalty factor on the accuracy, efficiency and stability of IGA are discussed.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103960"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145465503","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":"Data-driven topology-fiber shape optimization method for CFRP-winding buckle arrestor based on MG-cGAN","authors":"Jianxing Yu ,&nbsp;Zihang Jin ,&nbsp;Yang Yu ,&nbsp;Zhongzhen Sun ,&nbsp;Ruilong Gao ,&nbsp;Ruoke Sun","doi":"10.1016/j.marstruc.2025.103947","DOIUrl":"10.1016/j.marstruc.2025.103947","url":null,"abstract":"<div><div>To enhance the performance of deep-sea pipeline CFRP-winding buckle arrestors, this paper innovatively proposes a CFRP arrestor through joint topology-fiber shape optimization (TFSO). For the high cost of traditional joint optimization, a Multi-Generator conditional Generative Adversarial Network (MG-cGAN) is proposed to enable rapid TFSO prediction without iteration under limited high-cost TFSO dataset. Considering CFRP arrestor’s structural characteristics, the Bi-directional Evolutionary Structural Optimization (BESO) and Nondominated Sorting Genetic Algorithm III (NSGA-III) methods are sequentially employed for topology optimization (TO) and fiber shape optimization (FSO) to yield an improved structure form. Next, MG-cGAN method is used to construct a TFSO prediction model. In offline phase, TO and FSO prediction models are developed using Enhanced Structural Optimization Prediction Residual Network (ESOP-ResNet) based on single-form optimization results. In online phase, a TFSO prediction model is developed by combining TO and FSO predictions, with the model outputs treated as fake and limited serial TFSO results treated as real for adversarial training. Case studies demonstrate that the jointed optimized CFRP arrestor achieves a 25 % increase in arresting efficiency while reducing 40 % volume. Furthermore, MG-cGAN, coupled with ESOP-ResNet, significantly enhances optimization efficiency while maintaining high prediction accuracy, avoiding the substantial cost of constructing large TFSO result datasets.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103947"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158810","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":"From motion to moments: conditioning analysis of floating offshore wind turbine tower bending","authors":"Guy McCauley,&nbsp;Hugh Wolgamot,&nbsp;Paul H. Taylor,&nbsp;Jana Orszaghova","doi":"10.1016/j.marstruc.2025.103959","DOIUrl":"10.1016/j.marstruc.2025.103959","url":null,"abstract":"<div><div>The relationship between measured tower bending moments and motions of the TetraSpar Demonstrator floating offshore wind turbine is assessed using conditioning analysis techniques for an extreme storm event, and indicates that the motion to moment transfer function is linear, but dependent on turbine state and wind speed. Using measured motions and bending moments, a look-up table of linear transfer functions is generated for different turbine speed and wind speed bins. The look-up table is then used to predict tower bending moment from measured motions for a winter period, and the accuracy of the predictions is assessed. Finally, predicted stress from the linear transfer function method is used to calculate fatigue damage, which compares well to fatigue calculated using measured bending moments.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103959"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416840","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":"Study on the axial load recovery characteristics of damaged tensile armour layers in flexible marine cables","authors":"Qingzhen Lu ,&nbsp;Weining Wu ,&nbsp;Yuanchao Yin ,&nbsp;Yunxin Xie ,&nbsp;Bin Feng ,&nbsp;Jun Yan ,&nbsp;Hailong Lu","doi":"10.1016/j.marstruc.2025.103969","DOIUrl":"10.1016/j.marstruc.2025.103969","url":null,"abstract":"<div><div>In flexible marine cables, the axial load-bearing capacity of a damaged tensile armour layer tends to recover gradually along its axial length. The aim of this study is to determine the specific impact of tensile armour layer damage on axial load capacity, to analyse the axial mechanical behaviour of both intact and damaged tensile armour layers, and to obtain the recovery length after damage. A typical single-layer helically wound structure is selected as the research object, and a fully three-dimensional refined finite element model is established to simulate local damage and interlayer friction. Additionally, optical frequency domain reflectometry (OFDR) experimental analysis is employed to continuously observe the strain responses before and after damage, verifying the applicability of the finite element model and determining the load recovery length of the tensile armour layer under prefabricated damage conditions. Furthermore, key parameters affecting interlayer friction, including the friction coefficient, external pressure, and helical winding angle, are analysed. The results indicate that as the friction coefficient increases from 0.1 to 0.4, the external pressure increases from 0.25 MPa to 0.75 MPa, and the winding angle increases from 10° to 30°, the load recovery length decreases by 53.0 %, 43.9 %, and 44.3 %, respectively. This study provides scientific support for the operational maintenance of damaged tensile armour layers in flexible cables.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103969"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145579061","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":"Static load-bearing capacity of tubular K-joints reinforced with collar plates under axial loading","authors":"Hossein Nassiraei ,&nbsp;Hamid Reza Chavoshi ,&nbsp;Pooya Rezadoost","doi":"10.1016/j.marstruc.2025.103929","DOIUrl":"10.1016/j.marstruc.2025.103929","url":null,"abstract":"<div><div>This study investigates the static load-bearing performance of tubular K-joints (TKJs) reinforced with collar plates under axial loading. A detailed finite element model was developed incorporating 3D solid elements, weld geometry, contact nonlinearity, and both material and geometric nonlinear behavior. The model was validated against available experimental data, demonstrating excellent agreement. A comprehensive parametric study was then carried out on 128 tubular joints reinforced with collar plate (RTJs) to evaluate the influence of key dimensionless geometric parameters—such as brace-to-chord diameter ratio (<em>β</em>), chord slenderness ratio (<em>γ</em>), gap-to-chord diameter ratio (<em>ζ</em>), collar thickness ratio (<em>δ</em> = collar thickness to chord thickness), collar length ratio (<em>ω</em> = collar length to brace diameter), and brace inclination (<em>θ</em>)—on joint performance. Results show that the effectiveness of the reinforcement strongly dependent on geometry. Additionally, a nonlinear regression model based on yield volume theory was proposed to predict the reinforcement index (Φ), defined as the capacity ratio between RTJs and their unreinforced counterparts. The proposed formula provides a reliable tool for the design and evaluation of collar-reinforced tubular joints under axial loading.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103929"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046688","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":"An extended incremental-iterative approach to evaluate the residual ultimate strength of ship hull girders with welding residual stress subjected to cumulative plastic damage","authors":"Dongyang Li ,&nbsp;Zhen Chen","doi":"10.1016/j.marstruc.2025.103963","DOIUrl":"10.1016/j.marstruc.2025.103963","url":null,"abstract":"<div><div>Ship structures are normally assembled by a large number of structural components using welding technology which causes inevitable welding residual stress (WRS). Over the life span of a ship, the hull girder may be subjected to potential extreme cyclic bending in rough sea conditions. Cumulative plastic damage (CPD) induced by the repeated load reversals, coupled with the inherent WRS, may lead to significant deterioration of the ultimate hull girder strength. The current paper proposes an extended incremental-iterative approach to efficiently assess the residual ultimate strength of ship hull girders under the coupling effect of these two factors as well as material hardening. The developed approach follows the theoretical framework of traditional Smith’s method but extends its capability. A practical expression is suggested to analytically reformulate the load-shortening curves of structural elements by means of machine learning (ML). Influence of stiffener type, geometric dimension, WRS, load amplitude and cycle is considered in the modified curves. Experimental data, Common Structural Rules (CSR) formulae and numerical results by parametric nonlinear finite element analysis (FEA) are used to validate the extended incremental-iterative approach. It is found that this approach can predict the ultimate strength of simplified and real hull girders under different curvature amplitudes, loading sequences and cycle numbers. In addition, characteristics of the cyclic collapse responses of stiffener elements and hull girders are reported to provide novel insights into ship structural design.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103963"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145528176","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":"Evaluating numerical simulation accuracy for full-scale high-strength steel ship structures: Insights from the ISSC 2025 Ultimate Strength Committee benchmark on transversely stiffened panels","authors":"Marco Gaiotti Ph.D. ,&nbsp;Lars Brubak ,&nbsp;Bai-Qiao Chen ,&nbsp;Ionel Darie ,&nbsp;Dimitris Georgiadis ,&nbsp;Daisuke Shiomitsu ,&nbsp;Mihkel Kõrgesaar ,&nbsp;Yining Lv ,&nbsp;Ken Nahshon ,&nbsp;Marcelo Paredes ,&nbsp;Jani Romanoff ,&nbsp;Ingrid Schipperen ,&nbsp;Akira Tatsumi ,&nbsp;Murilo Vaz ,&nbsp;Yikun Wang ,&nbsp;Albert Zamarin ,&nbsp;Zhihu Zhan ,&nbsp;Jonas W. Ringsberg","doi":"10.1016/j.marstruc.2025.103966","DOIUrl":"10.1016/j.marstruc.2025.103966","url":null,"abstract":"<div><div>The demand for sustainable ship design has driven the use of high-strength steel to reduce structural weight, although this introduces buckling challenges due to unchanged elastic properties. Supported by the ISSC 2025 Ultimate Strength Committee, this study evaluated the ability of numerical simulations to predict the nonlinear response and ultimate strength of stiffened panels subjected to transverse compression. The benchmark consisted of full-scale blinded experimental tests that were conducted in parallel using a deck-like structure with thin plating prone to elastic buckling. The finite element models produced by participating researchers were compared, focusing on the complete end-shortening curve rather than just ultimate strength. Despite identical input geometry and minimal modeling guidance, results varied widely, revealing the significant influence of user-defined assumptions. The inclusion of additional data on material properties in the second study phase led to greater result dispersion due to the different strategies adopted for the hardening model. Key variability sources included the modeling of initial imperfections, material constitutive laws, and residual stresses from welding. The study highlights the need for consistent modeling and improved experimental data collection, particularly regarding boundary conditions and residual stress effects. While including welding stresses improved stiffness predictions, uncertainty in boundary behavior limited the assessment of ultimate strength impacts. The study also evaluated compliance with classification society rules (e.g., CSR, DNV, UR-S35), offering insights into how nonlinear numerical analyses complement or challenge regulatory frameworks based on closed-form expressions. Recommendations are made for improving simulation reliability and result validation.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103966"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145528178","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":"Study of bearing capacity and failure envelopes of SEPLA under combined loading","authors":"Jiang Tao Yi ,&nbsp;Zhi Hao Ye ,&nbsp;Qian Qian Cheng ,&nbsp;Chao Fan Liu ,&nbsp;Yu Ping Li ,&nbsp;Kai Yao ,&nbsp;Si Yu Li ,&nbsp;Tong Shen","doi":"10.1016/j.marstruc.2025.103938","DOIUrl":"10.1016/j.marstruc.2025.103938","url":null,"abstract":"<div><div>The suction embedded plate anchor (SEPLA) has gained prominence as an effective anchoring solution for offshore floating platforms, owing to its precise installation capabilities and superior load-bearing efficiency. Most existing literature primarily focuses on SEPLA's uniaxial bearing capacities under vertical (V), horizontal (H), or moment (M) loading. However, during the keying process or under extreme environmental conditions, SEPLA is often subjected to complex combinations of vertical, horizontal, and moment (VHM) loads, which is the primary motivation for this study. Using the coupled Euler-Lagrange (CEL) method, this study conducts a comprehensive large deformation finite element analysis of SEPLA under various combinations of vertical, horizontal, and moment loads, both pairwise and simultaneously. The study aims to determine the failure envelopes for load-bearing capacity under different loading combinations. A parametric analysis of these failure envelopes under various combined loading planes is performed. The results show that the anchor embedment depth, even after normalization, significantly influences the shape of the failure envelope, while the effects of anchor shape and interfacial friction are largely eliminated through normalization. A closed-form equation is developed to approximate the three-dimensional failure surface that dictates SEPLA’s bearing capacities under combined VHM loading. The findings of this research contribute to expanding the database for plate anchor bearing capacity under combined loading and provide a rational framework for estimating SEPLA's load-bearing capacity in design applications.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103938"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145059930","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 joint optimization by the combination of BPNN and NSGA-III for the polyester mooring system","authors":"Fasuo Yan ,&nbsp;Yuqing Du ,&nbsp;Yuyang Wang ,&nbsp;Wei Wang ,&nbsp;Dagang Zhang","doi":"10.1016/j.marstruc.2025.103942","DOIUrl":"10.1016/j.marstruc.2025.103942","url":null,"abstract":"<div><div>The design of a mooring system includes multiple variables such as the line’s span and number, orientation, segmentation, materials, counterweights, load conditions, and the requirements like dynamic performance, structural safety, and economic costs. Traditional optimization methods, relying on extensive analysis with professional tools, usually performed inefficiently after large scale computation and long-time post processing. In this study, a surrogate-assisted framework combining Back Propagation Neural Network (BPNN) models and the Non-dominated Sorting Genetic Algorithm III (NSGA-III) is proposed to the optimization of polyester mooring systems. An optimization model considering the common requirements of mooring system design was established and three independent surrogate models were developed for each objective among maximum tension, platform displacement and cable lines’ weight. Then, the NSGA-III was integrated with the surrogate models to select excellent combinations within the feasible sample space. The joint optimization by the combination of BPNN and NSGA-III was validated through a design case of polyester mooring system for a Floating Production Unit (FPU). As a result, it showed reliable prediction accuracy with errors below 5 % and time saving with 80 % less than normal operations. The results show that the proposed framework offers an efficient and accurate solution for mooring system optimization.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103942"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046691","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":"Asymmetric response analysis of large multi-body floating offshore platform in waves based on an improved CFD-FEA method","authors":"Nan Gu ,&nbsp;Xueqian Zhou ,&nbsp;Lei Li ,&nbsp;Huilong Ren","doi":"10.1016/j.marstruc.2025.103962","DOIUrl":"10.1016/j.marstruc.2025.103962","url":null,"abstract":"<div><div>The large multi-body floating offshore platform is a new type of offshore structure with a rectangular, long and flat shape. Traditional CFD-FEA methods, that use one backbone beam to simulate the stiffness of the whole floating offshore platform, is only applicable to symmetric response problems of floating offshore structure, specifically to vertical bending issues under head sea conditions, thus limiting its scope of application. In quartering seas, waves not only vary along the length of the offshore platform but also in the beam direction. The large multi-body floating offshore platform has a large breadth, resulting in a modest overall torsional stiffness. Under severe quartering sea conditions, the large multi-body floating offshore platform may undergo significant torsional deformation due to the substantial torsional moment induced by waves, presenting an asymmetric response problem. In the present paper, an improved CFD-FEA method based on backbone beam grid model composed of Timoshenko beams that can be used to simulate the vertical bending, horizontal bending, and longitudinal torsional motion of the offshore platform is developed for the analysis of asymmetric responses of large multi-body floating offshore platform. The hydrodynamic and structural response characteristics of the large multi-body floating offshore platform are studied experimental via a segmented model test, and also numerically using an improved CFD-FEA method. Comparisons of numerical results with experimental results show the validity of the proposed numerical simulation approach.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"106 ","pages":"Article 103962"},"PeriodicalIF":5.1,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145528177","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}