Applied Ocean Research最新文献

{"title":"Fatigue life characterisation of API X65 steel pipeline for internal vibrational loads under sea water condition","authors":"M.A. Khan ,&nbsp;S.S.K. Singh ,&nbsp;S. Abdullah ,&nbsp;A. Arifin ,&nbsp;M. Bashir","doi":"10.1016/j.apor.2025.104454","DOIUrl":"10.1016/j.apor.2025.104454","url":null,"abstract":"<div><div>The objective of this study is to characterise the fatigue life of API X65 steel based on the effects of corrosion and internal loads fluctuations using experimental and numerical analysis. The structural integrity of offshore in-service pipes is influenced by the existence of cracks resulting from many factors, such as random loads, material characteristics, welding imperfections, and corrosive influences. The internal pressure fluctuations for in-service oil and gas pipeline were experimentally and numerically analysed to determine the fatigue life based on stress life-based models from four test conditions. Mechanical testing was conducted on ASTM E8 specimens which were submerged in sea water for 48 h with pH: 6.8 and salinity: 28. 48ppt.From the scanning electron microscopy (SEM) the localised corrosion characteristics with cavities were observed. In addition, based on the cyclic test based on ASTM 466 were carried out, the endurance limit is found to be 276.3 MPa. The random operational stresses applied to the pipeline's material were used to predict the stress- based fatigue life of in-service pipeline by considering the mean stress correction models. The fatigue life was ranging from 1.15x<span><math><mrow><msup><mrow><mn>10</mn></mrow><mn>9</mn></msup><mspace></mspace></mrow></math></span>to 1.1x<span><math><mrow><msup><mrow><mn>10</mn></mrow><mn>11</mn></msup><mspace></mspace></mrow></math></span>cycles to failure, among them Goodman model showed the least fatigue life. Hence, the study provides an alternative approach to estimate fatigue life of in-service offshore pipelines using loading history and experimental results as a function of corrosion fatigue mechanism.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104454"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174570","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":"Influence of hydrostatic pressure on underwater explosion bubble-plate interaction","authors":"Lingxi Han ,&nbsp;Lintao Zhou ,&nbsp;Maria Mukhtar ,&nbsp;A-Man Zhang ,&nbsp;Rui Han ,&nbsp;Shuai Li","doi":"10.1016/j.apor.2025.104434","DOIUrl":"10.1016/j.apor.2025.104434","url":null,"abstract":"<div><div>This study examines the impact of hydrostatic pressure on the dynamics of underwater explosion bubbles near a steel plate through numerical and experimental studies. We conduct underwater explosion experiments in a pressure tank, altering the air pressure within the tank using a pressure pump to change the hydrostatic pressure around the bubbles. The interaction between the bubbles and the plate is recorded with a high-speed camera, and we extract and analyze the jet velocity, bubble radius, and plate displacement as functions of hydrostatic pressure. Building on this, we design a numerical framework that encompasses hydrostatic pressures varying from 0.2 MPa to 20 MPa and dimensionless bubble-plate standoff parameters <span><math><mi>γ</mi></math></span> from 0.6 to 2.5 for a more thorough investigation on the bubble-plate interaction. We find that both the maximum jet velocity and the maximum jet volume exhibit scaling relationships with hydrostatic pressure <span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> when <span><math><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi>∞</mi></mrow></msub><mo>&gt;</mo><mn>1</mn></mrow></math></span> MPa. Additionally, the dimensionless maximum jet volume shows a non-monotonic relationship with <span><math><mi>γ</mi></math></span>, depending on the degree of bubble-plate interaction at the moment of jet impact. Across a certain span, the maximum plate displacement also follows a scaling relationship with <span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span>, where the exponent differs according to <span><math><mi>γ</mi></math></span>. This work is intended to offer a foundation for the study of underwater explosion bubble dynamics and fluid–structure interaction characteristics under high hydrostatic pressure or deep water environments.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104434"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175794","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":"Data-driven remaining useful life estimation of subsea pipelines under effect of interacting corrosion defects","authors":"Soheyl Hosseinzadeh,&nbsp;Mohammadreza Bahaari,&nbsp;Mohsen Abyani,&nbsp;Milad Taheri","doi":"10.1016/j.apor.2025.104438","DOIUrl":"10.1016/j.apor.2025.104438","url":null,"abstract":"<div><div>This research presents a method for analyzing the Remaining Useful Life (RUL) of pipelines impacted by corrosion defects through the integration of Latin Hypercube Sampling (LHS), Finite Element Analysis (FEA), and Machine Learning (ML). A dataset consisting of 200 samples and 8 random variables is generated, representing various pipeline and corrosion defect specifications. Finite element modeling is performed using ABAQUS software and Python scripting to calculate the Failure Pressure and failure Maximum Von-Mises Stress (MVMS) under varying conditions of longitudinal spacing (<span><math><msub><mi>S</mi><mi>l</mi></msub></math></span>) and Internal Pressure (IP). This model generates a dataset that includes internal pressure, longitudinal spacing, and other relevant variables for the training and evaluation of ML models. Model performance is assessed through grid search and overfitting checks. A corrosion growth algorithm is incorporated to update input data dynamically, allowing for the prediction of future MVMS values and associated failure probabilities. The Probability of Failure (POF) is calculated, and Probability Density Functions (PDFs) for failure pressure are analyzed using standard distributions and Kolmogorov-Smirnov tests to identify the most accurate model. This approach provides a robust framework for predicting RUL by evaluating pipeline failures and probabilistic failure pressure over time, contributing valuable insights into the reliability and safety of pipeline systems under various conditions and time intervals.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104438"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143176387","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":"Wave attenuation by juvenile and mature mangrove Kandelia Obovata with flexible canopies","authors":"Cen Hang ,&nbsp;Junning Pan ,&nbsp;Liehong Ju ,&nbsp;Biyao Zhai ,&nbsp;Fan Yang ,&nbsp;Dongmei Xie","doi":"10.1016/j.apor.2025.104443","DOIUrl":"10.1016/j.apor.2025.104443","url":null,"abstract":"<div><div>Mangroves have notable wave attenuation capabilities, crucial for protecting coastal ecosystems. Most studies have focused on <em>Rhizophora,</em> particularly its complex aerial root systems, with limited research on <em>Kandelia obovata</em>, a widespread species characterized by short roots, radiating branches, and large canopies. To address this gap, wave attenuation by juvenile and mature <em>Kandelia obovata</em>, both with and without canopy, was investigated using wave flume experiments. The wave attenuation equation was modified to account for the complex mangrove morphology. The effective bulk drag coefficient of the entire vegetation <span><math><msub><mi>C</mi><mi>D</mi></msub></math></span>, the elastic branch <span><math><mrow><mi>C</mi><msubsup><mrow></mrow><mrow><mi>D</mi><mo>,</mo><mi>b</mi></mrow><mo>′</mo></msubsup></mrow></math></span> and flexible canopy <span><math><mrow><mi>C</mi><msubsup><mrow></mrow><mrow><mi>D</mi><mo>,</mo><mi>c</mi></mrow><mo>′</mo></msubsup></mrow></math></span> were calculated. The results highlight the wave energy attenuation capabilities of flexible canopy in both mature and juvenile cases.Even sparse canopy of juvenile mangroves can produce wave attenuation comparable to that of mature tree branches. Juvenile mangroves exhibit acceptable energy dissipation primarily due to their canopies, but only at low water levels. Both branches and canopies of mature mangroves significantly attenuate waves, but as water level increases, the canopy gradually dominates. A new parameter, the hydraulic length scale <span><math><mrow><mi>H</mi><mi>L</mi></mrow></math></span>, was proposed to predict the wave damping factor <em>β</em>. A new characteristic length scale hydrodynamic diameter <span><math><msub><mi>D</mi><mi>e</mi></msub></math></span> was used to calculate the vegetation Reynolds number <span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span> and the Keulegan-Carpenter number <span><math><mrow><mi>K</mi><mi>C</mi></mrow></math></span>. Principal component analysis (PCA) indicated that combining <span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span> and <span><math><mrow><mi>K</mi><mi>C</mi></mrow></math></span> best predicts <span><math><msub><mi>C</mi><mi>D</mi></msub></math></span>, with <em>Re</em> alone being the second-best. While <span><math><mrow><mi>C</mi><msup><mi>a</mi><mrow><mo>−</mo><mn>1</mn><mo>/</mo><mn>3</mn></mrow></msup></mrow></math></span> correlates with <span><math><mrow><mi>C</mi><msubsup><mrow></mrow><mrow><mi>D</mi><mo>,</mo><mi>c</mi></mrow><mo>′</mo></msubsup></mrow></math></span>, the underlying mechanism of this relationship may be complex and requires further research. The adaptability of the theoretical model for emergent vegetation is also explored. This study may contribute to the design of eco-coastal defenses using mangroves for protection.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104443"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174568","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":"Modelling the hydrodynamic response of a floating offshore wind turbine – a comparative study","authors":"Shimin Yu ,&nbsp;Edward Ransley ,&nbsp;Ling Qian ,&nbsp;Yang Zhou ,&nbsp;Scott Brown ,&nbsp;Deborah Greaves ,&nbsp;Martyn Hann ,&nbsp;Anna Holcombe ,&nbsp;Emma Edwards ,&nbsp;Tom Tosdevin ,&nbsp;Sudhir Jagdale ,&nbsp;Qian Li ,&nbsp;Yi Zhang ,&nbsp;Ningbo Zhang ,&nbsp;Shiqiang Yan ,&nbsp;Qingwei Ma ,&nbsp;Bonaventura Tagliafierro ,&nbsp;Salvatore Capasso ,&nbsp;Iván Martínez-Estévez ,&nbsp;Malin Göteman ,&nbsp;Javier L. Lara","doi":"10.1016/j.apor.2025.104441","DOIUrl":"10.1016/j.apor.2025.104441","url":null,"abstract":"<div><div>This paper summarises the work conducted within the 1st FOWT (Floating Offshore Wind Turbine) Comparative Study organised by the EPSRC (UK) ‘Extreme loading on FOWTs under complex environmental conditions’ and ‘Collaborative computational project on wave structure interaction (CCP-WSI)’ projects. The hydrodynamic response of a FOWT support structure is simulated with a range of numerical models based on potential theory, Morison equation, Navier-Stokes solvers and hybrid methods coupling different flow solvers. A series of load cases including the static equilibrium tests, free decay tests, operational and extreme focused wave cases are considered for the UMaine VolturnUS-S semi-submersible platform, and the results from 17 contributions are analysed and compared with each other and against the experimental data from a 1:70 scale model test performed in the COAST Laboratory Ocean Basin at the University of Plymouth. It is shown that most numerical models can predict similar results for the heave response, but significant discrepancies exist in the prediction of the surge and pitch responses as well as the mooring line loads. For the extreme focused wave case, while both Navier–Stokes and potential flow base models tend to produce larger errors in terms of the root mean squared error than the operational focused wave case, the Navier-Stokes based models generally perform better. Given the fact that variations in the solutions (sometimes large) also present in the results based the same or similar numerical models, e.g., OpenFOAM, the study highlights uncertainties in setting up a numerical model for complex wave structure interaction simulations such as those involving a FOWT and therefore the importance of proper code validation and verification studies.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104441"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174569","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":"The application of structured light for external subsea pipeline inspection based on the underwater dry cabin","authors":"Hai Zhu ,&nbsp;Jiawang Chen ,&nbsp;Yuan Lin ,&nbsp;Peng Zhou ,&nbsp;Kaichuang Wang ,&nbsp;Peiwen Lin ,&nbsp;Xiaoqing Peng ,&nbsp;Haonan Li ,&nbsp;Jin Guo ,&nbsp;Xueyu Ren ,&nbsp;Han Ge ,&nbsp;Zhonghui Zhou ,&nbsp;Yuping Fang ,&nbsp;Zhenjun Jiang ,&nbsp;Feng Gao ,&nbsp;Wendi Dai ,&nbsp;Xuehua Chen ,&nbsp;Guoming Cao ,&nbsp;Honghe Li ,&nbsp;Xu Gao ,&nbsp;Yuanjie Chen","doi":"10.1016/j.apor.2025.104431","DOIUrl":"10.1016/j.apor.2025.104431","url":null,"abstract":"<div><div>This study addresses the critical challenge of inspecting subsea pipelines in the highly turbid waters of the East China Sea, where visibility significantly hinders conventional methods. To overcome these limitations, we developed an advanced unmanned submarine light-scanning system that leverages structured light technology within a large-scale underwater dry cabin. This innovative setup enables high-precision, in-situ external inspections of pipelines by ensuring comprehensive scanning coverage even in poor visibility conditions. The core components of our system include the shipboard-controlled structured light scanning driving system (SLSDS) for precise motion control, enabling seamless full-pipeline coverage in a single deployment, and the shipboard electric control subsystem (SECS), which integrates power supply, sensing, communication, and control functionalities. Applied in the Zhoushan sea area, the dry-cabin scanning system demonstrated a 50–66.7 % reduction in inspection time and a tenfold improvement in data resolution over traditional technologies. These results highlight the system's effectiveness, efficiency, and safety advantages, offering a robust solution for pipeline inspections in offshore environments with compromised visibility. The system's capability to significantly enhance inspection accuracy and operational efficiency underscores its potential for broader application in similar high-turbidity settings.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104431"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143176384","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":"Solitary wave-induced 2D seepage effects on sediment incipient motion","authors":"Zhaojun Wang ,&nbsp;Junning Pan ,&nbsp;Biyao zhai ,&nbsp;Yue Zhao ,&nbsp;Yuerui Jin","doi":"10.1016/j.apor.2025.104456","DOIUrl":"10.1016/j.apor.2025.104456","url":null,"abstract":"<div><div>Solitary wave theory has been extensively applied to describe wave motions in very shallow water. Previous studies on sand movement induced by solitary waves have typically neglected the effects of seepage flow. This paper examines the effects of two-dimensional (2D) seepage on the Shields number using a semi-analytical model. A modified Shields number, incorporating seepage scaling factors, is derived to assess the influence of seepage forces on sediment incipience. It is found that wave-induced seepage can cause the maximum Shields number to increase by approximately 43.8 %, thereby promoting the incipience of seabed sediment. However, if only the vertical direction is considered, the downward \"injection\" force would reduce the Shields number. Ignoring the horizontal components of seepage may lead to an underestimation of seepage effects, potentially resulting in an inaccurate evaluation of sediment incipient motion. Parametric studies reveal that, under conditions of greater wave height, water depth, saturation, permeability, and lower Young’ s modulus, the maximum Shields number would noticeably increase due to the combined effects of horizontal and vertical seepage forces. The primary limitation is that the present results apply only to the laminar and partially transitioning regimes; further research is required for strong turbulence (<em>R</em>_e &gt; 5 × 10⁵).</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104456"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377397","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":"Simplified FELA-based evaluation of suction caisson bearing capacity in layered sands","authors":"Shili Ma ,&nbsp;Zhongling Zong ,&nbsp;Yifan Ji ,&nbsp;Yuwei Wei ,&nbsp;Liquan Xie","doi":"10.1016/j.apor.2025.104464","DOIUrl":"10.1016/j.apor.2025.104464","url":null,"abstract":"<div><div>Evaluating the bearing capacity of a foundation situated on layered soils is crucial for ensuring offshore wind structure stability under varied loading conditions in its service. This study uses finite element limit analysis (FELA) to investigate suction caisson behavior in one- and two-layered cohesionless soils from the Bohai Sea under purely vertical and combined loading. A key innovation is the introduction of a simplified method to analyze ultimate vertical bearing capacity, employing a theoretical retaining wall model that aligns closely with FELA results. The effective interface frictional angle is proposed as a parameter for assessing caisson performance under lateral loads and moments. The research also explores failure modes and combined load yield surfaces, considering soil layer thickness. The research indicates that as the internal friction angle of soils rises, the critical rupture angle for the active sliding body progressively increases, leading to the mobilization of deeper soil layers. The failure mode of suction caissons under lateral loading remains consistent, while moment loading results in deep rotational failure. Additionally, the study confirms the accuracy of existing elliptical equations in describing failure envelopes and introduces new findings on the influence of soil layer thickness on eccentricity parameters and failure envelope characteristics.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104464"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395546","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":"Neural prescribed-time dynamic positioning control of semi-submersible platforms with asymmetric input saturation","authors":"Chenfeng Huang,&nbsp;Yongsheng Dou,&nbsp;Zuojing Su,&nbsp;Xianku Zhang","doi":"10.1016/j.apor.2025.104444","DOIUrl":"10.1016/j.apor.2025.104444","url":null,"abstract":"<div><div>This paper presents an adaptive prescribed-time control scheme to the dynamic positioning (DP) system of semi-submersible platforms (SSPs) in the presence of asymmetric input saturation. To eliminate the adverse effect induced by the input saturation, a saturated compensating auxiliary system is introduced. The system singularity problem is removed by automatically enlarging and recovering the velocity error by implanting a modification saturated signals into the velocity error. The dynamic errors are transformed into a new error variable by using a fixed-time tracking performance function (FTTPF). After that, the fixed-time funnel boundaries (FTFBs) will no longer need to be redesigned according to various initial attitude errors. Meanwhile, the trajectories of the attitude errors are limited to the designed boundaries over a finite time interval. In addition, the new errors in the closed-loop system are guaranteed to be semi-global uniformly ultimately bounded (SGUUB). Finally, two simulations are performed to illustrate the effectiveness and superiority of the proposed scheme.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"155 ","pages":"Article 104444"},"PeriodicalIF":4.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143328412","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":"Optimization and performance analysis of a track tristable nonlinear energy sink subjected to impulsive, harmonic and sea wave excitations","authors":"Haobo Li ,&nbsp;Hu Ding ,&nbsp;Tienchong Chang ,&nbsp;Liqun Chen","doi":"10.1016/j.apor.2024.104404","DOIUrl":"10.1016/j.apor.2024.104404","url":null,"abstract":"<div><div>A traditional track nonlinear energy sink (TNES) is very sensitive to input energy. In order to extend effective energy threshold range of a TNES, a track tristable nonlinear energy sink (TTNES) with rotational inertia is proposed. Firstly, motion equations of a linear structure coupled with a TTNES are derived. The TTNES can translate into the track bistable NES (TBNES) and the track monostable NES (TMNES, traditional TNES) by adjusting track shape parameters. Secondly, equilibrium stability and bifurcation of a TTNES are determined. Then, analytical analysis and vibration reduction performance of a TTNES are conducted under impulsive excitations. In addition, approximate analysis and vibration reduction performance of a TTNES are carried out under harmonic excitations. Finally, a TTNES is applied to vibration mitigation of an offshore platform under sea wave excitations. The results show the TTNES exhibits better vibration reduction performance and higher robustness than traditional TNES when subjected to impulsive and harmonic excitations. In addition, the TTNES can effectively reduce the response of an offshore platform under sea wave excitations. This research provides the necessary theoretical basis for designing and applying the TTNES.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104404"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166406","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}