Marine Structures最新文献_第8页

Probabilistic demand models and analytical fragility quantification for ship hulls under ultimate bending conditions 船体在极限弯曲条件下的概率需求模型和分析脆性量化

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-24 DOI: 10.1016/j.marstruc.2025.103944

Aws Idris, Mohamed Soliman

Fragility analysis is a key performance assessment approach that quantifies the structural performance under a wide spectrum of possible hazard intensities. Fragility profiles can be established for a particular vessel using simulation techniques. However, simulation-based fragility assessment of ship hulls is computationally intensive, and its applicability is limited to the investigated vessel. In contrast, analytical fragility models provide a computationally efficient alternative allowing for wider applicability to cover a particular class of vessels. This paper proposes a novel framework for developing analytical fragility profiles for hulls of a specific vessel class considering ultimate bending conditions. The framework includes the development of probabilistic demand models needed to estimate the statistical characteristics of the engineering demand parameters based on the ship main particulars and hazard intensity measures. Nonlinear regression analysis, using constrained nonlinear optimization algorithms, is conducted to estimate the parameters of the proposed models. The framework is demonstrated on tankers, where probabilistic demand measures for five double-hull tankers are quantified while accounting for uncertainties in the applied loads and their combination factors. The capacity thresholds, representing the maximum demand a vessel can withstand before reaching a specific damage state, are then quantified probabilistically. Analytical fragility profiles are then established and validated against simulation-based fragility results obtained using artificial neural network-assisted finite element simulation. The results show that the developed probabilistic demand models can effectively estimate the statistical descriptors of the demand measure, and the established framework provides a highly computationally efficient alternative to simulation-based fragility assessment.

脆弱性分析是一种关键的性能评估方法，它可以量化结构在各种可能的危险强度下的性能。使用模拟技术可以建立特定船舶的易损性剖面。然而，基于仿真的船体易损性评估计算量大，其适用性仅限于被调查船舶。相比之下，分析脆弱性模型提供了一种计算效率高的替代方案，允许更广泛的适用性，以覆盖特定类别的船舶。本文提出了一种新的框架，用于开发考虑极限弯曲条件的特定船型船体的分析易损性剖面。该框架包括基于船舶主要特征和危害强度度量来估计工程需求参数的统计特征所需的概率需求模型的开发。采用约束非线性优化算法进行非线性回归分析，估计模型的参数。该框架在油轮上进行了演示，其中量化了五艘双壳油轮的概率需求度量，同时考虑了施加载荷及其组合因素的不确定性。容量阈值代表船舶在达到特定损坏状态之前可以承受的最大需求，然后以概率量化。然后，根据人工神经网络辅助有限元模拟获得的基于仿真的脆性结果，建立并验证分析脆性剖面。结果表明，所建立的概率需求模型能够有效地估计需求测度的统计描述符，所建立的框架为基于仿真的脆弱性评估提供了一种计算效率很高的替代方案。

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引用次数: 0

Damage-based strength reduction factor for seismic design of structures subjected to offshore ground motions 基于损伤的强度折减系数在近海地震动结构抗震设计中的应用

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-23 DOI: 10.1016/j.marstruc.2025.103945

Bali Liu , Hao Tian , Jinjun Hu , Changhai Zhai

This paper focuses on damage-based strength reduction factor (SRF) of single-degree-of freedom (SDOF) systems subjected to an ensemble of 892 offshore ground-motion records from the Kyoshin network in the Japan Sagami Bay Region. Damage-based SRF spectra are statistically developed considering both the offshore ground-motion characteristics (such as seafloor stations, magnitude, epicentral distance, significant duration and mean period) and structural parameters (including initial period, damage level, postyield stiffness ratio, ultimate ductility factor and hysteretic behavior). The differences in damage-based SRF spectra under offshore and onshore ground-motion records are also investigated. The results showed that the effects caused by offshore ground motions on the estimation of damage-based SRF are negligible, while the influence caused by the ultimate ductility factor can reach up to approximately 50 %. Analytical estimates of damage-based SRFs for mean level, 10th percentile values and 90th percentile values in terms of period, damage index, and ultimate ductility factor are proposed for the aseismic design of offshore structures.

本文研究了日本相模湾地区京信网892条海上地面运动记录对单自由度系统损伤强度折减系数的影响。基于损伤的SRF谱在统计上考虑了海上地震动特征（如海底台站、震级、震中距离、显著持续时间和平均周期）和结构参数（包括初始周期、损伤水平、场后刚度比、极限延性系数和滞后行为）。研究了基于损伤的SRF谱在陆上和海上地震动记录下的差异。结果表明，海上地震动对基于损伤的SRF估计的影响可以忽略不计，而极限延性系数的影响可达50%左右。提出了基于损伤的srf均值、第10百分位值和第90百分位值的周期、损伤指数和极限延性系数的分析估计，用于海上结构抗震设计。

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引用次数: 0

Corrigendum to “Analysis on the mechanical properties of TPJ foundation during scour development under different wave and current parameters” [Marine Structures, Volume 104, 15 October 2025, 103899] “不同波浪和水流参数下TPJ地基冲刷发展过程中的力学特性分析”的勘误[海洋结构，104卷，2025年10月15日，103899]

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-21 DOI: 10.1016/j.marstruc.2025.103943

Ning Wang , Ruihu Zhu , Qiming Wang , Siyuan He , Ling Qiu

引用次数: 0

Study of bearing capacity and failure envelopes of SEPLA under combined loading 复合荷载作用下SEPLA的承载力及破坏包络研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-15 DOI: 10.1016/j.marstruc.2025.103938

Jiang Tao Yi , Zhi Hao Ye , Qian Qian Cheng , Chao Fan Liu , Yu Ping Li , Kai Yao , Si Yu Li , Tong Shen

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.

由于其精确的安装能力和卓越的承载效率，吸式嵌入式板锚（SEPLA）作为一种有效的海上浮式平台锚固解决方案已经获得了突出的地位。大多数现有文献主要关注SEPLA在垂直(V)、水平(H)或弯矩(M)载荷下的单轴承载能力。然而，在键控过程中或在极端环境条件下，SEPLA经常受到垂直、水平和力矩（VHM）载荷的复杂组合，这是本研究的主要动机。本研究采用耦合欧拉-拉格朗日（CEL）方法，对SEPLA在垂直、水平、弯矩等不同载荷组合下的大变形进行了全面的有限元分析，包括竖向、水平和弯矩荷载的组合。研究的目的是确定在不同荷载组合下承载能力的破坏包络。对不同组合加载平面下的失效包络进行了参数化分析。结果表明：归一化后锚杆嵌入深度对破坏包络线形状的影响显著，而归一化后锚杆形状和界面摩擦力的影响基本消除；建立了三维破坏面近似的封闭方程，计算了复合VHM荷载作用下SEPLA的承载能力。本文的研究结果有助于扩充组合荷载作用下板锚承载力数据库，并为设计应用中预估板锚承载力提供合理框架。

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引用次数: 0

Bearing capacity of helical pile group foundation in clay over silty sand 粉质砂上黏土螺旋桩群基础承载力研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-12 DOI: 10.1016/j.marstruc.2025.103941

Yuxuan Wu , Mi Zhou , Xiangfeng Guo , Xihong Zhang , Jinhui Li

Recognized as a growing priority in offshore foundation engineering, helical piles demonstrate exceptional operational stability and lifecycle cost advantages, solidifying their role in modern marine infrastructure development. However, limited knowledge regarding the bearing capacity and failure mechanisms of helical pile group foundations under multi-directional loads in layered soils poses significant challenges for design and optimization of offshore wind platforms and other marine structures. This paper investigates the bearing capacity and failure mechanisms of the helical pile group foundation embedded in layered clay-over-silty-sand soil profiles using numerical simulation. The numerical model is validated against previously exhibiting published data before conducting a parameterized study. Key findings demonstrate that group configurations significantly enhance horizontal capacity compared to single piles, while clay-over-silty-sand stratification induces distinct delamination-type failure mechanisms of the soil around helical pile, contrasting with the global plastic flow observed in uniform clay. The study establishes the normalized bearing capacity envelopes for vertical-horizontal-moment (VHM) loading cases and provides algebraic equations to facilitate conservative design practices. These results offer valuable insights into optimizing the design of the helical pile group foundations for offshore wind platforms and other marine applications.

螺旋桩在海上基础工程中越来越受重视，它表现出卓越的运行稳定性和生命周期成本优势，巩固了其在现代海洋基础设施发展中的作用。然而，由于对层状土壤中螺旋桩群基础在多向荷载作用下的承载力和破坏机制了解有限，这对海上风电平台和其他海洋结构的设计和优化构成了重大挑战。本文采用数值模拟方法研究了层状粘土-粉砂地基中螺旋桩群地基的承载力及破坏机理。在进行参数化研究之前，对先前展示的已发表数据进行数值模型验证。主要研究结果表明，与单桩相比，群桩配置显著提高了水平承载力，而粘土-粉砂-粘土分层导致螺旋桩周围土体明显分层破坏机制，与均匀粘土中观察到的整体塑性流动相反。研究建立了竖向-水平弯矩（VHM）荷载情况下的归一化承载力包络，并提供了代数方程，便于保守设计实践。这些结果为海上风力平台和其他海上应用的螺旋桩群基础的优化设计提供了有价值的见解。

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引用次数: 0

A joint optimization by the combination of BPNN and NSGA-III for the polyester mooring system 基于BPNN和NSGA-III的聚脂系泊系统联合优化

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-12 DOI: 10.1016/j.marstruc.2025.103942

Fasuo Yan , Yuqing Du , Yuyang Wang , Wei Wang , Dagang Zhang

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.

系泊系统的设计包括多个变量，如缆绳的跨度和数量、方向、分段、材料、配重、负载条件以及动态性能、结构安全性和经济成本等要求。传统的优化方法依赖于专业工具的广泛分析，通常在大规模计算和长时间后处理后效率低下。本研究提出了一种结合反向传播神经网络（BPNN）模型和非支配排序遗传算法III （NSGA-III）的代理辅助框架，用于聚酯系泊系统的优化。建立了考虑系泊系统设计共同要求的优化模型，并针对最大张力、平台位移和缆绳重量三个目标分别建立了独立的替代模型。然后，将NSGA-III与代理模型相结合，在可行样本空间内选择最佳组合。通过浮式生产单元（FPU）聚酯系泊系统的设计实例，验证了BPNN与NSGA-III联合优化的有效性。结果表明，该方法预测精度可靠，误差小于5%，比常规操作节省时间80%。结果表明，该框架为系泊系统优化提供了一种高效、准确的解决方案。

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引用次数: 0

Ship bow impact force in head-on collision 船艏正面碰撞时的冲击力

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-12 DOI: 10.1016/j.marstruc.2025.103940

Shengming Zhang , Preben Terndrup Pedersen

This paper presents simplified analysis procedures for ship (with bulbous bow) bow impact force and bow damage assessment in ship head-on collisions. The theoretical background for ship bow crushing analysis is described and the result is expressions for the crushing force and bow damage as a function of an impact strength. The impact strength, depending on the internal stiffening of the ship bow and materials, is determined by two different approaches: Approach A- uses world-wide published experimental model test data; Approach B- uses theoretical calculation results from crushing analyses of full-scale sea-going ships. Applying these data for the impact strength into the theory, formulas for bow impact forces and bow damages are developed. The formulations are compared with published existing methods and validated with the data from full-scale ship collision accidents and FEA simulation results. The developed procedure has a sound physical foundation and can be used as a tool in risk analyses of ship-ship collisions, ship collisions against offshore structures such as oil and gas installations and windfarms, and bridge structures.

本文给出了球首船舶正面碰撞中船首冲击力和船首损伤评估的简化分析方法。阐述了船首破碎分析的理论背景，给出了破碎力和船首损伤随冲击强度的函数表达式。冲击强度取决于船首和材料的内部加强程度，由两种不同的方法确定：方法A-使用世界范围内公布的实验模型测试数据；方法B-采用全尺寸海船破碎分析的理论计算结果。将这些冲击强度数据应用到理论中，建立了弓的冲击力和弓的损伤计算公式。将这些公式与已有的方法进行了比较，并用实际船舶碰撞事故数据和有限元模拟结果进行了验证。所开发的程序具有良好的物理基础，可作为船舶碰撞风险分析工具，用于船舶与海上结构（如石油和天然气设施、风力发电场和桥梁结构）的碰撞。

引用次数: 0

Static load-bearing capacity of tubular K-joints reinforced with collar plates under axial loading 轴向载荷作用下带接箍板的k形管节点静承载力研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-11 DOI: 10.1016/j.marstruc.2025.103929

Hossein Nassiraei , Hamid Reza Chavoshi , Pooya Rezadoost

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 (β), chord slenderness ratio (γ), gap-to-chord diameter ratio (ζ), collar thickness ratio (δ = collar thickness to chord thickness), collar length ratio (ω = collar length to brace diameter), and brace inclination (θ)—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.

本文研究了轴向载荷作用下带接箍板的管状k形节点的静力承载性能。建立了包含三维实体单元、焊缝几何、接触非线性以及材料和几何非线性行为的详细有限元模型。该模型与现有的实验数据进行了验证，证明了良好的一致性。对128个带箍板加固的管状节点进行了综合参数化研究，评估了关键的无量因几何参数——箍与弦径比（β）、弦长细比（γ）、间隙与弦径比（ζ）、箍厚比（δ =箍厚与弦厚）、箍长比（ω =箍长与托径）和箍斜（θ）对节点性能的影响。结果表明，加固效果与几何形状有很大关系。此外，提出了基于屈服体积理论的非线性回归模型来预测加固指数（Φ），定义为钢筋混凝土与未加固混凝土的容量比。该公式为轴向载荷作用下箍筋管状节点的设计与评价提供了可靠的工具。

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引用次数: 0

Artificial neural network model to assist in design of ship stiffened plates considering ultimate strength 考虑极限强度的船舶加筋板设计中的人工神经网络模型

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-11 DOI: 10.1016/j.marstruc.2025.103939

Im-jun Ban , Sang-jin Oh , Minjoon Kim , Jeong-Hyeon Kim , Sung-chul Shin

The ship structure is exposed to combined loading conditions during operational exposure to waves due to the hull weight, cargo weight, and other loads. Because the primary structural members of the ship structure are stiffened plates, securing structural safety during the ship design stage is critical. However, in the current design method, the results are inaccurate and inefficient in terms of the required time or cost owing to the poor preparation of the physical model or assumptions regarding the boundary conditions. To resolve this, the present study performs a structural analysis on 3000 stiffened plates with included initial imperfections and subjected to axial compression, which causes the buckling loads on the ship. Deep learning database is constructed based on the finite element analysis results. Then, deep learning model is developed to propose an effective method for predicting the ultimate strength of the stiffened plates. The prediction results of the deep learning method showed similarity with the FE analysis results. During the initial design stage, the structural designer can use this model to determine the geometrical properties of the stiffened plate within a reasonable time and cost. In addition, these results can potentially be used in the reverse engineering of vessels.

由于船体重量、货物重量和其他载荷的影响，船舶结构在操作过程中暴露于波浪的组合载荷条件下。由于船舶结构的主要结构构件是加劲板，因此在船舶设计阶段确保结构的安全至关重要。然而，在目前的设计方法中，由于物理模型的准备或对边界条件的假设不充分，在所需的时间或成本方面，结果是不准确和低效的。为了解决这个问题，本研究对3000块加筋板进行了结构分析，其中包括初始缺陷，并受到轴向压缩，这导致了船舶的屈曲载荷。基于有限元分析结果构建深度学习数据库。在此基础上，建立了深度学习模型，提出了一种预测加筋板极限强度的有效方法。深度学习方法的预测结果与有限元分析结果相似。在初始设计阶段，结构设计人员可以利用该模型在合理的时间和成本内确定加筋板的几何性能。此外，这些结果可以潜在地用于船舶的逆向工程。

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引用次数: 0

Ice loads on a bottomless cylinder under dynamic wave action: An experimental study 动波作用下无底圆筒冰载荷的实验研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-09-06 DOI: 10.1016/j.marstruc.2025.103902

Hongtao Li , Ersegun D. Gedikli , Zhengshun Cheng , Junji Sawamura , Raed Lubbad , Wenjun Lu

In this study, we report the results of a comprehensive experimental analysis of ice loads on a bottomless cylinder under dynamic wave action and explore advanced methods to identify, isolate, and quantify these loads. To achieve this, we investigate and discuss various system identification techniques, such as the Prony method, dynamic mode decomposition (DMD), and covariance-driven stochastic subspace identification (SSI-cov), highlighting their applicability to experimental data. We also employ advanced signal processing approaches, including Robust Principal Component Analysis (RPCA) and robust local regression, to separate ice loads from quasi-periodic wave loads. Our findings reveal that ice and wave loads exhibit a positive correlation with wave height. Further, when the wave height remains unchanged, the normalized collision duration increases with wave frequency and shows insignificant dependence on peak ice loads. Additionally, ice loads are found to be

3 \sim 4

times larger than wave loads. These results contribute to advancing our understanding of wave–ice–structure interactions and provide practical insights for designing resilient offshore structures in ice-infested waters.

在这项研究中，我们报告了在动力波浪作用下无底圆柱体上冰载荷的综合实验分析结果，并探索了识别、隔离和量化这些载荷的先进方法。为了实现这一目标，我们研究和讨论了各种系统识别技术，如proony方法、动态模态分解（DMD）和协方差驱动的随机子空间识别（SSI-cov），并强调了它们对实验数据的适用性。我们还采用了先进的信号处理方法，包括鲁棒主成分分析（RPCA）和鲁棒局部回归，以分离冰载荷和准周期波载荷。我们的研究结果表明，冰和波浪荷载与浪高呈正相关。当波高不变时，归一化碰撞持续时间随波频增加而增加，与峰值冰荷载的关系不明显。此外，冰荷载比波浪荷载大3 ~ 4倍。这些结果有助于提高我们对波浪-冰-结构相互作用的理解，并为在结冰水域设计弹性离岸结构提供实用的见解。

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引用次数: 0